Mathcounts 2020 Countdown Round #1-10

The Sharks have a win-loss record of 36-14. What percent of the games played have the Sharks won?

How many minutes are there in half of a day?

Tags

CCSS.4.MD.A.1

A certain gameboard consists of an n × n array of squares. Vijay places a token on every square that does not border an edge of the board. If Vijay uses exactly 169 tokens, what is the value of n?

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CCSS.8.EE.A.2

What is the greatest common factor of the first 100 positive prime numbers?

This week, Rudy began saving his $5 weekly allowance to buy a new gaming system. How many weeks worth of allowance must Rudy save to buy a gaming system that costs $299?

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CCSS.3.OA.A.3

Triangle ABC has perimeter 24 cm and area 20 cm $^2$  . Triangle DEF is similar
to triangle ABC and has area 45 cm $^2$  . What is the perimeter of triangle DEF, in centimeters?

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CCSS.7.G.A.1

If Colin can wrap a gift in 18 seconds, how many minutes will it take him to wrap 100 gifts?

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CCSS.3.MD.A.1

What number is halfway between  $\frac{6}{7}$   and  $\frac{6}{7}$   ? Express your answer as a common fraction. 

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CCSS.7.NS.A.1C

For what value of k does the straight line passing through the points (4k + 1, 3k + 2) and (3k + 2, 2k + 1) have slope 2?

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CCSS.8.EE.B.5

George has five ribbons, each 4 feet 8 inches in length. What is the combined length of George’s ribbons? Express your answer to the nearest foot.

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CCSS.4.MD.A.2