I believe it’s the second & fourth one
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<u><em>The correct answer is: </em></u>4.
<u><em>Explanation</em></u><span>
<u><em>: </em></u>To find this answer, we divide the number of windows, 50, by the length (in windows covered) of each covering, 15:
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This means that 3 coverings won't quite be long enough, so we will need 4. </span></span>
The box of detergent has a lower cost per pound
Well, there are 3 feet in a yard so you can just divide the number of yards by 3.