2019 AMC 10B Problems/Problem 11
Problem
Two jars each contain the same number of marbles, and every marble is either blue or green. In Jar 1 the ratio of blue to green marbles is 9:1, and the ratio of blue to green marbles in Jar 2 is 8:1. There are 95 green marbles in all. How many more blue marbles are in Jar 1 than in Jar 2?
Solution
Call the amount of marbles in each jar x, because they are equivalent. Thus, x/10 is the amount of green marbles in 1, and x/9 is the amount of green marbles in 2. x/9+x/10=19x/90, 19x/90=95, and x=450 marbles in each jar. Because the 9/10 is the amount of blue marbles in jar 1, and 8/9 is the amount of blue marbles in jar 2, 9x/10-8x/9=x/90, so there must be 5 more marbles in jar 1 than jar 2. The answer is A
See Also
| 2019 AMC 10B (Problems • Answer Key • Resources) | ||
| Preceded by Problem 10 |
Followed by Problem 12 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
| All AMC 10 Problems and Solutions | ||
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