Difference between revisions of "1996 AJHSME Problems/Problem 15"
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To determine a remainder when a number is divided by <math>5</math>, you only need to look at the last digit. If the last digit is <math>0</math> or <math>5</math>, the remainder is <math>0</math>. If the last digit is <math>1</math> or <math>6</math>, the remainder is <math>1</math>, and so on. | To determine a remainder when a number is divided by <math>5</math>, you only need to look at the last digit. If the last digit is <math>0</math> or <math>5</math>, the remainder is <math>0</math>. If the last digit is <math>1</math> or <math>6</math>, the remainder is <math>1</math>, and so on. | ||
− | To determine the last digit of <math>1492\cdot 1776\cdot 1812\cdot 1996</math>, you only need to look at the last digit of each number in the product. Thus, we compute <math>2\cdot 6\cdot 2\cdot 6 = 12^2 = 144</math>. The last digit of the number <math>1492\cdot 1776\cdot 1812\cdot 1996</math> is also <math>4</math>, and thus the remainder when the number is divided by <math>5</math> is also <math>4</math>, which gives an answer of <math>\boxed{E}</math>. | + | To determine the last digit of <math>1492\cdot 1776\cdot 1812\cdot 1996</math>, you only need to look at the last digit of each number in the product. Thus, we compute <math>2\cdot 6\cdot 2\cdot 6 = 12^2 = 144</math>. The last digit of the number <math>1492\cdot 1776\cdot 1812\cdot 1996</math> is also <math>4</math>, and thus the remainder when the number is divided by <math>5</math> is also <math>4</math>, which gives an answer of <math>\boxed{E}</math>. |
==See Also== | ==See Also== |
Revision as of 09:16, 3 December 2022
Problem
The remainder when the product is divided by 500 is
Solution
To determine a remainder when a number is divided by , you only need to look at the last digit. If the last digit is or , the remainder is . If the last digit is or , the remainder is , and so on.
To determine the last digit of , you only need to look at the last digit of each number in the product. Thus, we compute . The last digit of the number is also , and thus the remainder when the number is divided by is also , which gives an answer of .
See Also
1996 AJHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 14 |
Followed by Problem 16 | |
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All AJHSME/AMC 8 Problems and Solutions |
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