1955 AHSME Problems/Problem 3
Problem
If each number in a set of ten numbers is increased by , the arithmetic mean (average) of the ten numbers:
Solution 1
Let the sum of the 10 numbers be x. The mean is then . Then, since you're adding 20 to each number, the new sum of the numbers is x+200, since there are 10 numbers. Then, the new mean is , which simplifies to , which is .
See Also
1955 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 2 |
Followed by Problem 4 | |
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