Robin is traveling from one end of a forest to the other

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Robin is traveling from one end of a forest to the other. In order to find her way back, she is leaving morsels of bread in the following pattern: 2 morsels of wheat, 3 morsels of white, and one morsel of rye. The pattern repeats after she leaves the morsel of rye. If Robin drops 2,000 morsels of bread, what are the last 3 morsels of bread that she drops?

A. rye - wheat - wheat
B. wheat - wheat - white
C. white - rye - wheat
D. white - white - white
E. white - white - rye

The OA is A.

In a single round, Robin drops 6 morsels.

Remainder (2000/6) = 2

Final action = 2 drops of wheat --> Option B, C, D, and E can be eliminated.

Can anyone explain another way to solve this PS question? Thanks!
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by [email protected] » Thu Mar 29, 2018 3:13 pm
Hi All,

We're told that the morsels of bread are dropped in the following pattern: 2 morsels of wheat, 3 morsels of white, and one morsel of rye. Since the pattern REPEATS after she leaves the morsel of rye, this is essentially a 'remainder' question. We're asked for the last 3 morsels of bread at the end of 2000 morsels.

The pattern can be visualized as WWHHHR where W = wheat, H = white and R = rye

With 2000 morsels, we have 2000/6 = 333 r 2... meaning that there are 333 complete groups of 6 and two extra morsels (which would represent the first two morsels of the next group of 6). Those extra two morsels are BOTH wheat. The morsel that appears before those extra two is the last morsel from a full group of 6 (re: a morsel of rye).

Thus, the final 3 morsels are: rye, wheat, wheat.

Final Answer: A

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