Question

A toy store sells either small dolls or large dolls. If one person buys 6 small dolls and 5 large dolls and spends $65, and another person buys 5 small dolls and 4 large dolls and spends $53, how much does each type of dolls cost?

Answer 1

each small doll cost 6.5 dollars and each large doll cost 10 dollars

Answer 2

6 small dolls + 5 large dolls = $65 ------------------ (1) 
5 small dolls + 4 large dolls = $53 ------------------ (2)

(1) x 5 : 30 small dolls + 25 large dolls = $325 ------------------ (1a) 
(2) x 6 : 30 small dolls + 24 large dolls = $318 ------------------ (2a)

(1a) - (2a) : 1 large doll = $7

Substitute 1 large doll = $7 into (1):

6 small dolls + 5(7)  = $65
6 small dolls + 35  = $65
6 small dolls = $65 - $35
6 small dolls = $30
1 small doll  = $5

Answer: 1 small doll is $5 and I large doll is $7.