If 10 glasses cost 40 dollars, how much do 18 glasses cost?

$72

Step-by-step explanation:

Let's set up a proportion using the following setup:

We know that it costs $40 for 10 glasses.

We don't know the cost for 18 glasses. Therefore, we can say it costs for 18 glasses.

We are trying to solve for , the cost of 18 glasses. Therefore, we must isolate it.

is being divided by 18. The inverse of division is multiplication. Multiply both sides of the equation by 18.

x= $72

18 glasses cost $72.00