A neghborhood lemonade stand sold small glasses lemonade for 15cts a glass and a large gas for 25 cts a glass. ?
Let the amount of small glasses be x, let the number of large glasses be y.
Based on the given information in the problem, we can make two equations:
a) .15x + .25 y = 105 (small glasses are 15 cents, large glasses are 25 cents, and the total dollar amount sold is 105 dollars.
b) x + y = 500 (500 glasses were sold which means the number of small and large glasses MUST add to 500.
Let’s manipulate b) so that we isolate one of the variables i. e. :
y = 500 - x.
Now we substitute this value in for y in equation a) to make:
.15x + .25 (500 - x) = 105
==> .15 x + 125 - .25 x = 105
==> -.1 x = -20
==> x = 200.
==> y = 300. (from equation b)
So 200 small glasses and 300 large glasses were sold.