Answer:
A. 17 1/2 . . . cubic feet
Explanation:
The volume is the product of the length, width, and height. If your calculator doesn't deal with mixed numbers, it can be convenient to use one that does.
(4 ft)(2 1/2 ft)(1 3/4 ft) = 17 1/2 ft³
The volume of the box is 17 1/2 cubic feet.
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You can also convert the numbers to decimal to use on your calculator:
4 × 2.5 × 1.75 = 17.500
Or convert them to improper fractions:
4 × 5/2 × 7/4 = 35/2 = 17 1/2