"Published in Newark, California, USA"
A cylindrical tin can holding 2 gal. has its height equal to the diameter of its base. Another cylindrical tin can with the same capacity has its height equal to twice the diameter of its base. Find the ratio of the amount of tin required for making the two cans with covers.
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 volume of a tin can in cubic inches is
If the height of a tin can equals its diameter, then the diameter is
Hence, the total area of a tin can is
If the height of a tin can is twice its diameter, then the diameter is
Hence, the total area of a tin can is
Therefore, the ratio of the amount of tin required for making the two cans with covers is
