2019 AMC 10B Problems/Problem 11
Contents
Problem
Two jars each contain the same number of marbles, and every marble is either blue or green. In Jar the ratio of blue to green marbles is , and the ratio of blue to green marbles in Jar is . There are green marbles in all. How many more blue marbles are in Jar than in Jar ?
Solution 1
Call the number of marbles in each jar (because the problem specifies that they each contain the same number). Thus, is the number of green marbles in Jar , and is the number of green marbles in Jar . Since , we have , so there are marbles in each jar.
Because is the number of blue marbles in Jar , and is the number of blue marbles in Jar , there are more marbles in Jar than Jar . This means the answer is .
Solution 2 (Completely Solve)
Let , , , , represent the amount of blue marbles in jar 1, the amount of green marbles in jar 1, the the amount of blue marbles in jar 2, and the amount of green marbles in jar 2, respectively. We now have the equations, , , , and . Since and , we substitute that in to obtain . Coupled with our third equation, we find that , and that . We now use this information to find and .
Therefore, so our answer is . ~Binderclips1
~LaTeX fixed by Starshooter11 ~Typo fixed by Little
Solution 3
Writing out to ratios, we have in jar and in jar . Since the jar must have to same amount of marbles, let's make a variable and for each of the ratios to be multiplied by. Now we would have . We can take the most obvious values of and and then scale it from there. We should be able to see that and could be and respectively. Now remember that there are green marbles or for some integer to scale it. Substituting and dividing, we find . Thus to find the difference of the blue marbles we must do
~ Wiselion
Video Solution
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Video Solution
https://youtu.be/DzQZtQvNDwA?t=9
Video Solution
See Also
2019 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 10 |
Followed by Problem 12 | |
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All AMC 10 Problems and Solutions |
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