Difference between revisions of "2021 Fall AMC 10A Problems/Problem 18"
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==Risky, but Quick Solution== | ==Risky, but Quick Solution== | ||
The top right box has <math>4</math> choices and the top left box has <math>3</math> choices. Thus, it is reasonable to assume that the answer is a multiple of <math>12</math>. We know that the answer will not be too small or too large, so the answer is <math>\boxed{\textbf{(C)}\ 84}</math> | The top right box has <math>4</math> choices and the top left box has <math>3</math> choices. Thus, it is reasonable to assume that the answer is a multiple of <math>12</math>. We know that the answer will not be too small or too large, so the answer is <math>\boxed{\textbf{(C)}\ 84}</math> | ||
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+ | - Aidensharp |
Revision as of 18:43, 22 November 2021
Problem
A farmer's rectangular field is partitioned into by
grid of
rectangular sections as shown in the figure. In each section the farmer will plant one crop: corn, wheat, soybeans, or potatoes. The farmer does not want to grow corn and wheat in any two sections that share a border, and the farmer does not want to grow soybeans and potatoes in any two sections that share a border. Given these restrictions, in how many ways can the farmer choose crops to plant in each of the four sections of the field?
[asy]
draw((0,0)--(100,0)--(100,50)--(0,50)--cycle);
draw((50,0)--(50,50));
draw((0,25)--(100,25));
[/asy]
Risky, but Quick Solution
The top right box has choices and the top left box has
choices. Thus, it is reasonable to assume that the answer is a multiple of
. We know that the answer will not be too small or too large, so the answer is
- Aidensharp