MathDB
Change in the Sum of the Numbers in a Set

Source:

June 13, 2009

Problem Statement

A set of n n numbers has the sum s s. Each number of the set is increased by 20 20, then multiplied by 5 5, and then decreased by 20 20. The sum of the numbers in the new set thus obtained is: (A)\ s \plus{} 20n\qquad (B)\ 5s \plus{} 80n\qquad (C)\ s\qquad (D)\ 5s\qquad (E)\ 5s \plus{} 4n