Answer: 13
Step-by-step explanation:
Well actually
13
and a half, but we are assuming he needs full pieces, so
13
shelves.
This is simple division:
Mr. Gengel needs shelves that are
1
1
3
feet long and has an
18
foot long board. In order to determine how many shelves he can make you must divide:
18
÷
1
1
3
=
13.5
You can't have half a shelf so you round down to
1