The average of 10 numbers is -10. If the sum of 6 of them is 100, what is the average of the other 4 ?

On a certain French-American committee, 2/3 of the members are men, and 3/8 of the men are Americans, If 3/5 o...

At 3 A.M. the temperature was 13 degree below zero. By noon, it had risen to 32. What was the average hourly i...

In January, the value of a stock increased by 25%, and in February, it decreased by 20%.How did the value of t...

The population of a country doubled every 10 years from 1960 to 1990. What was the percent increase in populat...

On a test consisting of 80 questions, Nasir answered 75% of the first 60 questions correctly. What percent of...

A hospital has enough pills on hand to treat 10 patients 14 days. How long will the pills last if their are 35...