To do this we take the outlier off the parenthesis (the 4) and multiply it by the two numbers inside the parenthesis...
4*7 + 4*8
28+32
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Find 10 reams
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1 ream = 32 ounces
10 reams = 32 x 10
10 reams = 320 ounces
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Convert ounce to pound:
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1 ounce = 0.0625
10 ounces = 0.0625 x 10
10 ounces = 0.625 pounds
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Answer: Each case weighs 0.625 pound.
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Left 4. Or x-4 because the way it moves