exam Maths Puzzle Numerical Ability

I am comlpetley lost at how to begin to solve this problem
here is the question
4/3 = 8
-
b

the way it is written in the book is 4/3 divided by b equals 8

Read Solution (Total 0)

exam Other Question

(36) Ride the peaks. Smith bicycled 45 miles going from Durango, and Jones bicycled 70 miles. Jones averaged 5 miles per hour more than Smith, and his trip took one-half hour longer thank Smith’s. How fast was each one traveling? Solve the system by substitution.
x + y = 12
y = 2x

This problem has me a bit confused and need some help. Thanks.