1985 AJHSME Problems/Problem 21
Contents
Problem
Mr. Green receives a raise every year. His salary after four such raises has gone up by what percent?
Solution
Assume his salary is originally dollars. Then, in the next year, he would have dollars, and in the next, he would have dollars. The next year he would have dollars and in the final year, he would have . As the total increase is greater than , the answer is .
~sakshamsethi
Solution 2
Let Mr.Green's salary be dollars.
Notice Mr.Green's salary is a geometric sequence with common ratio
Apply the general term formula for geometric sequences, after four years, Mr.Green's salary becomes which is .
is more than , thus the answer is
~ lovelearning999
See Also
1985 AJHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 20 |
Followed by Problem 22 | |
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