1951 AHSME Problems/Problem 28
Problem
The pressure of wind on a sail varies jointly as the area of the sail and the square of the velocity of the wind. The pressure on a square foot is pound when the velocity is miles per hour. The velocity of the wind when the pressure on a square yard is pounds is:
Solution
Because varies jointly as and , that means that there is a number such that . You are given that when and . That means that . Then, substituting into the original equation with and (because a square yard is times a square foot), you get . Solving for , we get , so . Hence, the answer is .
See Also
1951 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 27 |
Followed by Problem 29 | |
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