"Published in Newark, California, USA"
An ice-storage plant removed from the center of a pond a mass of ice covering an area of 2 acres. If the ice had a uniform thickness of 2 ft., find the weight in tons of the ice removed. (Ice weighs 56 lbs. per cu. ft.; 1 ton = 2,240 lbs.; 1 acre = 43,560 sq. ft.)
Solution:
To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
The area of the base which is the top of ice covering from the center of a pond is
The volume of an ice covering which is a cylinder is
The weight of an ice covering is
Therefore, the weight of an ice covering in metric tons is
