The ratio of the cost of a tennis racket to tennis balls is 18: 1. if a can of balls cost $5.35, what is the cost of the racket?

Racket to ball ratio is 18:1 ; 18 is racket and 1 is ball. Ratio can also be shown as fraction 18/1.
Ball cost 5.35. If ball in ratio is represented by the 1, then ball cost is on denominator. r will represent racket cost.
r/5.35
Equation:
18/1 = r/5.35
Cross multiply
96.3 = r

Racket cost is $96.30

2xy/9 is the answer to this problem