Question 1176251
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Here is an alternative to the standard algebraic method for solving problems like this as shown by the other tutor.<br>
The least common multiple of the two given times is 90 minutes.<br>
In 90 minutes the first clerk could stock 90/30 = 3 shelves; the other could stock 90/45 = 2 shelves.<br>
So together in 90 minutes the two clerks could stcok 3+2=5 shelves; that means they can stock the one shelf if 90/5 = 18 minutes.<br>