Question

A 2 1/2 inch nail is driven through a 1 1/8 inch thick piece of wood supporting a joist. How far into the joist did it extend?

Answer 1

It extended the joist by 1 3/8 .

Answer 2

Answer:
`1(3)/(8)` inches

Explanation:

Given: The length of nail =
`2(1)/(2)\ \text{inch}`

The thickness of the wood =
`1(1)/(8)\ \text{inch}`

The length extended by nail =
`2(1)/(2)-1(1)/(8)` inch

First convert the mixed fractions into the improper fraction, we get

⇒The length extended by nail =
`(5)/(2)-(9)/(8)` inch

⇒The length extended by nail =
`(5*4-9)/(8)=(20-9)/(8)` inches

⇒The length extended by nail =
`(11)/(8)=1(3)/(8)` inches