Question

A carpenter has a plank 8 1/5 feet long. How many feet should be cut off to make a plank 5 7/8 feet long?

Answer 1

2 13/40 feet or 2.325 ft

Step-by-step explanation:

The length of the plank = 8⅕ feet

To determine many feet should be cut off, subtract 5⅞ feet from 8⅕ feet.

`8(1)/(5)-5(7)/(8)`

Step 1: Convert both fractions to improper fractions.

`=(41)/(5)-(47)/(8)`

Step 2: Find the lowest common multiple of the denominators 8 and 5.

`\begin{gathered} =(41(8)-47(5))/(40) \\ =(328-235)/(40) \\ =(93)/(40) \\ =2(13)/(40)\text{ feet} \end{gathered}`

2 13/40 feet of the plank should be cut off.