I buy x choc ices and y orange ices and spend $2.30. I buy ten ices altogether . the choc ices cost $0.30 each and the orange ices cost $0.20 each. How many of each do I buy?

I understand how to get to two equations from the problem. All the equations thatI tried are not working out. Please help me out!

1 Answer
Mar 22, 2018

3 chocolate ices and 7 orange ices

Explanation:

So the two equations that you are going to make are as follows. The first is about amount, the second is about cost .

Since you bought 10 total, this is the first equation:
x + y = 10

Since chocolate ice costs "30 cents" (or 30/100 of a dollar) and orange ice costs "20 cents" (or 20/100 of a dollar) we can make this equation:

0.30x + 0.20y = 2.30

I'm actually going to multiply that whole equation by 10 to move the decimal points one places and make it easier to solve:

3x + 2y = 23

Now rearrange the first equation to substitute into the second:
x + y = 10
x = 10 - y

Now substitute:
3x + 2y = 23
3(10-y) + 2y = 23
30 - 3y + 2y = 23
30 - y = 23
-y = - 7
y = 7

You bought 7 orange ices.

Now put the value of y into an equation to solve for x
x = 10 - y
x = 10 - 7
x = 3

You bought 3 chocolate ices.