2017 AMC 10B Problems/Problem 5
Contents
Problem
Camilla had twice as many blueberry jelly beans as cherry jelly beans. After eating 10 pieces of each kind, she now has three times as many blueberry jelly beans as cherry jelly beans. How many blueberry jelly beans did she originally have?
Solution
Solution 1
Denote the number of blueberry and cherry jelly beans as and
respectively. Then
and
. Substituting, we have
, so
,
.
Solution 2
From the problem, we see that 10 less than one of the answer choices must be a multiple of 3 and positive. The only answer choice satisfying this is . We can check that 40 blueberry and 20 cherry jelly beans indeed does work.
Video Solution
~savannahsolver
Video Solution by the Beauty of Math
With new whiteboard at home: https://www.youtube.com/watch?v=zTGuz6EoBWY
~icematrix
2017 AMC 10B (Problems • Answer Key • Resources) | ||
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Followed by Problem 6 | |
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