"Published in Newark, California, USA"
A packaging box 2.2 ft. by 4.9 ft. by 5.5 ft. is to be completely covered with tin. How many square feet of the metal are needed? (Neglect waste for seams, etc.)
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 |
If a packaging box is completely covered with tin, then the amount of metal used is equal to the total area of a packaging box. The total area of a packaging box is equal to
