You can
put this solution on YOUR website!Bolt size b must be

plus or minus

.
Therefore, the smallest acceptable size will be

and the largest acceptable size will be

. This means that the bolt size must be

. I'm not sure from the wording here whether or not we accept the endpoints. If so, then the answer will be

. Also, I'm not sure whether you are supposed to find a common denominator and express as single fractions. You'll have to let me know if you need to add and subtract the fractions.
R^2 at SCC