Calculate the length of bolt required to fasten four pieces of steel together. Have answer need explanation as to how.

Question

The nut is ¾", the washer is 3/8" thick and the bolt must extend 1/4" beyond the nut. The four pieces of steel are 1/4", 3/8", 5/16" and 3/16" thick.

Can someone explain how the answer is 2 1/2. Thanks.

Answer 1

First, the total thickness of the steel=(4+6+5+3)/16=18/16" when all the individual thicknesses are based on the numbers of sixteenths. The bolt head is separated from the first piece of steel by the washer, which adds another ⅜", that is, 6/16". The nut secures the bolt to the bottom piece of steel and adds another 12/16", and the bolt must extend 4/16" beyond the nut. So we are adding (6+12+4)/16=22/16" to 18/16"=40/16"=5/2"=2½".