How to simply 11/20 in fraction form

If the cost to mail a package is an initial $5 and $0.28 for every pound the total cost to mail a package was $11.27, how much did the package weigh?

The following division is being performed using multiplication by the reciprocal find the missing numbers is 5/12 divided by x/3 equals 5/12 times x/10 equals 1/x

Micheal is 4 times as old as brandon and is also 27 years older than brandon. how old is micheal