MATHCOUNTS 2023 Countdown #11-20

The total amount Raven paid for a book was $9.45, which included a 5% sales tax. What was the pre-tax price of the book, in dollars?

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CCSS.7.EE.A.2

CCSS.7.EE.B.3

CCSS.7.EE.B.4

CCSS.7.RP.A.3

What percentage of positive integer divisors of 120 are even?

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CCSS.7.EE.B.3

CCSS.7.RP.A.3

You have 6 blue shirts, 5 red shirts, 2 white shirts, 9 black shirts, 12 green shirts and 4 yellow shirts. If you randomly select one shirt, what is the probability you select a blue, black, or white shirt? Express your answer as a common fraction.

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CCSS.7.SP.C.5

CCSS.7.SP.C.7

A palindrome is a word or number that is the same when the letters or numbers are arranged in reverse order. For example, the word "racecar" and the number 1221 are palindromes. What is the largest palindrome smaller than 1,000,000 in which no digit occurs more than 2 times?

Two integers have a sum of 100 and a product of 2400. What is their absolute difference?

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CCSS.7.EE.B.3

CCSS.7.EE.B.4

Manny is thinking of a number. If Manny's number is divided by 13, then multiplied by 11, then decreased by 12, and then added to 73, the result is 94. What is Manny's original number?

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CCSS.7.EE.A.1

CCSS.7.EE.A.2

CCSS.7.EE.B.3

CCSS.7.EE.B.4

If a 1/2-cup serving of oatmeal contains 150 calories, how many cups of oatmeal are needed for a portion of 200 calories? Express your answer as a common fraction.

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CCSS.7.EE.B.3

CCSS.7.NS.A.2

CCSS.7.NS.A.3

CCSS.7.RP.A.2

CCSS.7.RP.A.3

If A, B, and C are distinct positive integers, what is the least possible value of the expression (A + B) - (A - B) + (B + C) - (B - C)?

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CCSS.6.EE.A.2

CCSS.6.EE.A.3

CCSS.6.EE.B.6

The sum of three distinct primes is 14. What is the product of these primes?

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CCSS.6.EE.B.5

CCSS.6.EE.B.6

All segments in the figure shown have length 2 cm and meet at right angles. What is the area of the figure, in square centimeters?

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CCSS.7.G.B.6