Can you give me some step-by-step instructions for this math problem: Vincent can buy flowers in packages of 3 for $2.50 or in packages of 2 for $1. How much money does he save by buying 18 flowers at the better price?
Find how many packages of 3 would be needed which is 18 ÷ 3 = 6.
The cost of using packages of 3 is 6 × $2.50 = $15.
Find how many packages of 2 would be needed which is 18 ÷ 2 = 9.
The cost of using packages of 2 is 9 × $1 = $9.
Vincent would save $15 - $9 = $6.