Answer:
504 nails
Explanation:
To calculate how many nails the contractor will need for 18 sheets of plywood, we can first find out how many nails she used for one sheet of plywood and then multiply that by 18.
She used 4 sheets of plywood and 112 nails to construct one wall, so for one sheet of plywood, she used:112 nails / 4 sheets = 28 nails per sheet
Now, to find out how many nails she will need for 18 sheets of plywood, you can multiply the nails per sheet by the number of sheets:28 nails/sheet * 18 sheets = 504 nails
The contractor will need 504 nails to construct walls with 18 sheets of plywood in two rooms.