"Published in Newark, California, USA"
Two rectangular water tanks with tops on the same level are connected by a pipe through their bottoms. The base of one is 6 in. higher than that of the other. Their dimensions are 4 ft. by 5 ft. by 2½ ft. and 4 ft. by 7 ft. by 3 ft., respectively. How deep is the water in the larger tank when the water they contain equals half their combined capacity, if the 2½ ft. and 3 ft. edges are vertical?
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 total volume of two empty rectangular water tanks is
If two tanks are filled with water which is equal to one-half of the total volume of two empty tanks, the above figure becomes
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| Photo by Math Principles in Everyday Life |
Therefore, from the figure above, the depth or height of water in the larger tank is
