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โIf ( x ) is a real number and ( lceil x rceil = 14 ), how many possible values are there for ( lceil x^2 rceil )?
๐กOkay, so I have this problem here: If ( x ) is a real number and ( lceil x rceil = 14 ), how many possible values are there for ( lceil x^2 rceil )? Hmm, let's break this down step by step.First, I remember that the ceiling function ( lceil x rceil ) gives the smallest integer greater than or equal to ( x ). So if ( lceil x rceil = 14 ), that means ( x ) is somewhere between 13 and 14, but not including 14. Wait, actually, no. Let me think again. If the ceiling of ( x ) is 14, then ( x ) must be greater than 13 but less than or equal to 14. So, ( 13 < x leq 14 ). Yeah, that makes sense because if ( x ) were exactly 14, the ceiling would still be 14, but if ( x ) were 13 or less, the ceiling would be 13 or lower.Okay, so ( x ) is in the interval ( (13, 14] ). Now, I need to find the possible values of ( lceil x^2 rceil ). That means I need to find all the possible integer values that ( x^2 ) can take when ( x ) is in that interval, and then take the ceiling of those values.Let me first figure out the range of ( x^2 ). If ( x ) is just a little bit more than 13, say 13.1, then ( x^2 ) would be ( 13.1^2 = 171.61 ). On the other hand, if ( x ) is exactly 14, then ( x^2 = 196 ). So, ( x^2 ) ranges from just above ( 13^2 = 169 ) up to ( 14^2 = 196 ). Therefore, ( x^2 ) is in the interval ( (169, 196] ).But wait, ( x ) is strictly greater than 13, so ( x^2 ) is strictly greater than ( 13^2 = 169 ). So, ( x^2 ) is in ( (169, 196] ). Now, since ( lceil x^2 rceil ) is the smallest integer greater than or equal to ( x^2 ), the possible values of ( lceil x^2 rceil ) would be the integers from the smallest integer greater than 169 up to 196.The smallest integer greater than 169 is 170, and the largest integer in the range is 196. So, ( lceil x^2 rceil ) can take any integer value from 170 to 196, inclusive.Now, to find how many integers are there from 170 to 196 inclusive, I can subtract 170 from 196 and add 1 (since both endpoints are included). So, ( 196 - 170 = 26 ), and ( 26 + 1 = 27 ). Therefore, there are 27 possible integer values for ( lceil x^2 rceil ).Wait, let me double-check that. If I list the numbers from 170 to 196, how many are there? Starting at 170, then 171, 172, ..., up to 196. The count is ( 196 - 170 + 1 = 27 ). Yeah, that seems right.But hold on, is there any possibility that ( x^2 ) might not reach all the way up to 196? Since ( x ) can be exactly 14, ( x^2 ) can be exactly 196, so ( lceil x^2 rceil ) can indeed be 196. Similarly, since ( x ) is greater than 13, ( x^2 ) is greater than 169, so the smallest ceiling value is 170. Therefore, all integers from 170 to 196 are achievable.I think that's solid. So, the number of possible values for ( lceil x^2 rceil ) is 27.
โThe ratio of the number of games won to the number of games lost (no games ending in a tie nor cancelled) by the High Flyers is 17/8. If it is known that 6 games were cancelled, and these cancelled games are additional to the games either won or lost, to the nearest whole percent, what percent of its games did the team lose?A) 20%B) 30%C) 35%D) 40%
๐กAlright, so I have this problem here about the High Flyers' games. The ratio of games won to games lost is 17 to 8, and there were 6 games that were cancelled. I need to find out what percent of their games they lost, and round it to the nearest whole percent. The options are 20%, 30%, 35%, or 40%. Okay, let's break this down. First, the ratio of games won to games lost is 17:8. That means for every 17 games they won, they lost 8 games. So, if I think about it, the total number of games they played (excluding the cancelled ones) would be 17 plus 8, which is 25 games. But wait, there were also 6 games that were cancelled. The problem says these cancelled games are additional to the games they won or lost. So, does that mean the total number of games they were supposed to play is the 25 games plus the 6 cancelled ones? That would make the total number of games 31. So, out of these 31 games, they actually played 25 games and lost 8 of them. To find the percentage of games lost, I need to divide the number of games lost by the total number of games scheduled, including the cancelled ones. Let me write that down:Percentage lost = (Number of games lost / Total number of games scheduled) ร 100Plugging in the numbers:Percentage lost = (8 / 31) ร 100Hmm, let me calculate that. 8 divided by 31 is approximately 0.258. Multiplying that by 100 gives me about 25.8%. Wait, but the options don't have 25.8%. The closest one is 30%. But maybe I did something wrong here. Let me double-check my steps.First, the ratio is 17:8, so total games played are 17 + 8 = 25. Then, adding the 6 cancelled games, total scheduled games are 25 + 6 = 31. So, 8 losses out of 31 total games. Calculating 8 divided by 31 again: 8 รท 31 โ 0.258, which is about 25.8%. Rounding that to the nearest whole percent would be 26%. But 26% isn't one of the options. The closest option is 30%. Maybe I interpreted the problem incorrectly. Let me read it again. It says the ratio of games won to games lost is 17/8, and 6 games were cancelled, additional to the games won or lost. So, the total number of games scheduled is games won plus games lost plus cancelled games. So, if I let the number of games won be 17k and games lost be 8k for some integer k, then total games scheduled would be 17k + 8k + 6 = 25k + 6. Then, the percentage lost would be (8k / (25k + 6)) ร 100. Hmm, this introduces a variable k. Maybe I need to find the value of k that makes the percentage closest to one of the options. Let me try k = 1: 8 / (25 + 6) = 8/31 โ 25.8%, which is still 26%.k = 2: 16 / (50 + 6) = 16/56 โ 28.57%, which is about 29%.k = 3: 24 / (75 + 6) = 24/81 โ 29.63%, which is about 30%.k = 4: 32 / (100 + 6) = 32/106 โ 30.19%, which is about 30%.k = 5: 40 / (125 + 6) = 40/131 โ 30.53%, which is about 31%.So, as k increases, the percentage approaches 32/25 = 1.28, which is 32%. But since k has to be an integer, the percentage varies between 25.8% and 32%. Looking at the options, 30% is the closest to the values we're getting for k = 3, 4, and 5. So, I think the answer is 30%.But wait, the problem doesn't specify the value of k, so maybe I need to assume k = 1 for simplicity. But then the percentage is 25.8%, which isn't an option. Alternatively, maybe the total number of games is just 25, and the 6 cancelled games are separate. So, total games scheduled are 25 + 6 = 31, and the percentage lost is still 8/31 โ 25.8%. But since 25.8% isn't an option, and 30% is the closest, I think the answer is 30%.Yeah, I think that's it. The team lost approximately 30% of their games.
โA tank is 25 m long, 12 m wide, and 6 m deep. The cost of plastering its walls and bottom at 75 paise per sq. m is how much?
๐กFirst, I need to determine the surface area that requires plastering. The tank has four walls and a bottom. The two longer walls are each 25 meters long and 6 meters deep, while the two shorter walls are each 12 meters wide and 6 meters deep. The bottom of the tank is 25 meters long and 12 meters wide.Next, I'll calculate the area of each type of wall and the bottom:- The area of one long wall is 25 meters multiplied by 6 meters, which equals 150 square meters. Since there are two long walls, their combined area is 300 square meters.- The area of one short wall is 12 meters multiplied by 6 meters, which equals 72 square meters. With two short walls, their combined area is 144 square meters.- The area of the bottom is 25 meters multiplied by 12 meters, totaling 300 square meters.Adding these areas together gives the total surface area to be plastered: 300 square meters (long walls) + 144 square meters (short walls) + 300 square meters (bottom) = 744 square meters.The cost of plastering is 75 paise per square meter. Converting 75 paise to rupees, since 100 paise equals 1 rupee, 75 paise is 0.75 rupees.Finally, multiplying the total surface area by the cost per square meter will give the total cost: 744 square meters multiplied by 0.75 rupees per square meter equals 558 rupees.
โThere are 6 more female students than male students in a club. If the total number of the club is 82, how many female students are there?
๐กFirst, I'll define the number of male students as ( M ) and the number of female students as ( F ).According to the problem, there are 6 more female students than male students, so I can write the equation:[ F = M + 6 ]The total number of students in the club is 82, which gives me another equation:[ M + F = 82 ]Next, I'll substitute the first equation into the second equation to eliminate ( F ):[ M + (M + 6) = 82 ]Combining like terms, I get:[ 2M + 6 = 82 ]Subtracting 6 from both sides:[ 2M = 76 ]Dividing both sides by 2 to solve for ( M ):[ M = 38 ]Now that I know there are 38 male students, I'll find the number of female students by adding 6:[ F = 38 + 6 = 44 ]Therefore, there are 44 female students in the club.
โThe notation overline{abc} represents a three-digit number in decimal form. If overline{abc} is equal to the sum of all two-digit numbers formed by the digits a, b, c, find all the three-digit numbers that satisfy this condition.
๐กAlright, so I have this problem where I need to find all three-digit numbers (overline{abc}) such that the number itself is equal to the sum of all two-digit numbers formed by its digits (a), (b), and (c). Hmm, okay, let's break this down step by step.First, let me make sure I understand the notation. (overline{abc}) represents a three-digit number where (a) is the hundreds digit, (b) is the tens digit, and (c) is the units digit. So, mathematically, this number can be expressed as (100a + 10b + c).Now, the problem states that this three-digit number is equal to the sum of all two-digit numbers formed by the digits (a), (b), and (c). Let me figure out what all those two-digit numbers are. Since we have three digits, the possible two-digit numbers we can form are:1. (10a + b)2. (10a + c)3. (10b + a)4. (10b + c)5. (10c + a)6. (10c + b)So, there are six two-digit numbers in total. The sum of these numbers should be equal to the original three-digit number (overline{abc}). Let me write that equation out:[100a + 10b + c = (10a + b) + (10a + c) + (10b + a) + (10b + c) + (10c + a) + (10c + b)]Okay, now I need to simplify the right side of this equation. Let's compute each term:1. (10a + b)2. (10a + c)3. (10b + a)4. (10b + c)5. (10c + a)6. (10c + b)Adding them all together:[(10a + b) + (10a + c) + (10b + a) + (10b + c) + (10c + a) + (10c + b)]Let me combine like terms. First, the terms with (a):- (10a + 10a + a + a = 22a)Next, the terms with (b):- (b + 10b + 10b + b = 22b)And the terms with (c):- (c + c + 10c + 10c = 22c)So, the total sum of the two-digit numbers is:[22a + 22b + 22c]I can factor out the 22:[22(a + b + c)]Wait, hold on, that seems a bit off. Let me double-check my addition:Looking back at the terms:- For (a): (10a + 10a + a + a = 22a) (correct)- For (b): (b + 10b + 10b + b = 22b) (correct)- For (c): (c + c + 10c + 10c = 22c) (correct)Yes, that's right. So the sum is indeed (22(a + b + c)).But wait, the original equation was:[100a + 10b + c = 22(a + b + c)]Hmm, that seems a bit too straightforward. Let me write it out:[100a + 10b + c = 22a + 22b + 22c]Now, let's bring all terms to one side to simplify:[100a + 10b + c - 22a - 22b - 22c = 0]Simplify each term:- (100a - 22a = 78a)- (10b - 22b = -12b)- (c - 22c = -21c)So, the equation becomes:[78a - 12b - 21c = 0]Hmm, that's a bit messy. Maybe I can simplify this equation by dividing through by a common factor. Let's see:78, 12, and 21 all share a common factor of 3.Dividing each term by 3:[26a - 4b - 7c = 0]Okay, that's better. So, the equation simplifies to:[26a = 4b + 7c]Now, I need to find all digits (a), (b), and (c) (each from 0 to 9, with (a) at least 1 since it's a three-digit number) that satisfy this equation.Let me think about how to approach this. Since (a), (b), and (c) are digits, their possible values are limited, so maybe I can try plugging in possible values for (a) and see if I can find corresponding (b) and (c) that satisfy the equation.Given that (a) is a digit from 1 to 9, let's consider each possible value of (a) and see what (4b + 7c) must equal.Starting with (a = 1):[26(1) = 4b + 7c implies 26 = 4b + 7c]Now, I need to find integers (b) and (c) (each from 0 to 9) such that (4b + 7c = 26).Let me try different values of (c) and see if (4b) becomes a multiple of 4.Starting with (c = 0):(4b = 26 - 0 = 26) โ (b = 26/4 = 6.5) โ Not an integer.(c = 1):(4b = 26 - 7 = 19) โ (b = 19/4 = 4.75) โ Not an integer.(c = 2):(4b = 26 - 14 = 12) โ (b = 12/4 = 3) โ Integer! So, (b = 3), (c = 2).Let me check if this works:(4(3) + 7(2) = 12 + 14 = 26) โ Correct.So, one solution is (a = 1), (b = 3), (c = 2), which gives the number 132.Let me see if there are more solutions for (a = 1).(c = 3):(4b = 26 - 21 = 5) โ (b = 5/4 = 1.25) โ Not an integer.(c = 4):(4b = 26 - 28 = -2) โ Negative (b), which isn't possible.So, only one solution for (a = 1).Moving on to (a = 2):[26(2) = 4b + 7c implies 52 = 4b + 7c]Again, let's try different (c) values.(c = 0):(4b = 52 - 0 = 52) โ (b = 13) โ But (b) must be a single digit (0-9). Not possible.(c = 1):(4b = 52 - 7 = 45) โ (b = 45/4 = 11.25) โ Not an integer.(c = 2):(4b = 52 - 14 = 38) โ (b = 38/4 = 9.5) โ Not an integer.(c = 3):(4b = 52 - 21 = 31) โ (b = 31/4 = 7.75) โ Not an integer.(c = 4):(4b = 52 - 28 = 24) โ (b = 24/4 = 6) โ Integer! So, (b = 6), (c = 4).Check: (4(6) + 7(4) = 24 + 28 = 52) โ Correct.So, another solution is (a = 2), (b = 6), (c = 4), giving the number 264.Let me check higher (c) values for (a = 2):(c = 5):(4b = 52 - 35 = 17) โ (b = 17/4 = 4.25) โ Not an integer.(c = 6):(4b = 52 - 42 = 10) โ (b = 10/4 = 2.5) โ Not an integer.(c = 7):(4b = 52 - 49 = 3) โ (b = 3/4 = 0.75) โ Not an integer.(c = 8):(4b = 52 - 56 = -4) โ Negative (b), not possible.So, only one solution for (a = 2).Proceeding to (a = 3):[26(3) = 4b + 7c implies 78 = 4b + 7c]Again, trying different (c) values.(c = 0):(4b = 78 - 0 = 78) โ (b = 78/4 = 19.5) โ Not a digit.(c = 1):(4b = 78 - 7 = 71) โ (b = 71/4 = 17.75) โ Not a digit.(c = 2):(4b = 78 - 14 = 64) โ (b = 64/4 = 16) โ Not a digit.(c = 3):(4b = 78 - 21 = 57) โ (b = 57/4 = 14.25) โ Not a digit.(c = 4):(4b = 78 - 28 = 50) โ (b = 50/4 = 12.5) โ Not a digit.(c = 5):(4b = 78 - 35 = 43) โ (b = 43/4 = 10.75) โ Not a digit.(c = 6):(4b = 78 - 42 = 36) โ (b = 36/4 = 9) โ Integer! So, (b = 9), (c = 6).Check: (4(9) + 7(6) = 36 + 42 = 78) โ Correct.So, another solution is (a = 3), (b = 9), (c = 6), giving the number 396.Let me check higher (c) values for (a = 3):(c = 7):(4b = 78 - 49 = 29) โ (b = 29/4 = 7.25) โ Not an integer.(c = 8):(4b = 78 - 56 = 22) โ (b = 22/4 = 5.5) โ Not an integer.(c = 9):(4b = 78 - 63 = 15) โ (b = 15/4 = 3.75) โ Not an integer.So, only one solution for (a = 3).Moving on to (a = 4):[26(4) = 4b + 7c implies 104 = 4b + 7c]Trying different (c) values.(c = 0):(4b = 104 - 0 = 104) โ (b = 26) โ Not a digit.(c = 1):(4b = 104 - 7 = 97) โ (b = 97/4 = 24.25) โ Not a digit.(c = 2):(4b = 104 - 14 = 90) โ (b = 90/4 = 22.5) โ Not a digit.(c = 3):(4b = 104 - 21 = 83) โ (b = 83/4 = 20.75) โ Not a digit.(c = 4):(4b = 104 - 28 = 76) โ (b = 76/4 = 19) โ Not a digit.(c = 5):(4b = 104 - 35 = 69) โ (b = 69/4 = 17.25) โ Not a digit.(c = 6):(4b = 104 - 42 = 62) โ (b = 62/4 = 15.5) โ Not a digit.(c = 7):(4b = 104 - 49 = 55) โ (b = 55/4 = 13.75) โ Not a digit.(c = 8):(4b = 104 - 56 = 48) โ (b = 48/4 = 12) โ Not a digit.(c = 9):(4b = 104 - 63 = 41) โ (b = 41/4 = 10.25) โ Not a digit.So, no solutions for (a = 4).Similarly, for (a = 5):[26(5) = 4b + 7c implies 130 = 4b + 7c]Trying (c = 0):(4b = 130) โ (b = 32.5) โ Not a digit.(c = 1):(4b = 123) โ (b = 30.75) โ Not a digit.(c = 2):(4b = 116) โ (b = 29) โ Not a digit.Continuing this way, it's clear that (b) will exceed 9 for all (c) values, so no solutions here.Similarly, for (a = 6):[26(6) = 4b + 7c implies 156 = 4b + 7c]Again, (c = 0):(4b = 156) โ (b = 39) โ Not a digit.And this pattern continues, with (b) only increasing as (a) increases, so no solutions for (a = 6) to (a = 9).Therefore, the only solutions are when (a = 1), (a = 2), and (a = 3), giving the numbers 132, 264, and 396.Let me just verify one of these to make sure I didn't make a mistake.Take 132:Digits are (a = 1), (b = 3), (c = 2).Sum of two-digit numbers:(13 + 12 + 31 + 32 + 21 + 23)Calculating each:- (13)- (12)- (31)- (32)- (21)- (23)Adding them up:(13 + 12 = 25)(25 + 31 = 56)(56 + 32 = 88)(88 + 21 = 109)(109 + 23 = 132)Yes, that checks out.Similarly, let's check 264:Digits (a = 2), (b = 6), (c = 4).Sum of two-digit numbers:(26 + 24 + 62 + 64 + 42 + 46)Calculating each:- (26)- (24)- (62)- (64)- (42)- (46)Adding them up:(26 + 24 = 50)(50 + 62 = 112)(112 + 64 = 176)(176 + 42 = 218)(218 + 46 = 264)Perfect, that works too.And finally, 396:Digits (a = 3), (b = 9), (c = 6).Sum of two-digit numbers:(39 + 36 + 93 + 96 + 63 + 69)Calculating each:- (39)- (36)- (93)- (96)- (63)- (69)Adding them up:(39 + 36 = 75)(75 + 93 = 168)(168 + 96 = 264)(264 + 63 = 327)(327 + 69 = 396)Yes, that also checks out.So, after going through each possible value of (a) and solving for (b) and (c), I found that the only three-digit numbers satisfying the condition are 132, 264, and 396.
โIn Township K, each property is taxed at a certain percentage of its assessed value. If the assessed value of a property in Township K is increased from 20,000 to 28,000, the property tax will increase by 800. What is the tax rate as a percentage of the assessed value?
๐กFirst, I need to determine the tax rate as a percentage of the assessed value in Township K.I know that the assessed value of the property increased from 20,000 to 28,000, which is an increase of 8,000.The property tax increased by 800 due to this increase in assessed value.To find the tax rate, I can set up the equation:8,000 * r = 800Solving for r:r = 800 / 8,000 = 0.1To express this as a percentage, I multiply by 100:0.1 * 100 = 10%Therefore, the tax rate as a percentage of the assessed value is 10%.