Question

Christy bought an 8-foot piece of lumber to trim a bookshelf. Altogether, she needs 100 inches of lumber for the trim. Did Christy buy enough lumber?

Answer 1

No unless she cuts the piece of lumber in half lengthwise.

Explanation:

`8 ft xx ( (12 "inches") /(1 ft)) = 96 "` inches.

`96< 100`

So she does not have enough lumber.

Answer 2

No

Explanation:

One foot is the same length as 12 inches

So, as we have 8 feet we have 8 lots of 12 inches

8 is `2xx2xx2` so we have:

`color(red)(8)xx12`

`color(red)(2xx2xx2)xx12`

`=2xx2xx24 larr" the first multiplication by 2"`

`=2xx48 larr" the second multiplication by 2"`

`=96 larr" the third multiplication by 2"`

So 8 feet is the same length as 96 inches.

This is not enough as the target is 100 inches