Question

Matthew bought flowers for his mom. he bought 12 flowers that were a combination of roses and lilies. the roses cost $1.75 each and the lilies cost $2.00 each. he spent $21.75. how many of each flower did he buy?

Answer 1

The correct answer is 9 roses and 3 lilies

Answer 2

To solve this problem you must apply the proccedure shown below:

1. Let's call:
`x` the number of roses and
`y` the number of lilies.

2. You must make a system of equation based on the information given in the problem above:

`1) 1.75x+2y=21.75\\ 2) x+y=12`

3. Use the method of substitution. First, solve for
`x` in the second equation, then substitute it into the first equation, and then solve for
`y`:

`x=12-y\\ 1.75(12-y)+2y=21.75\\ y=3`

4. Now, substitute
`y=3` into the second equation:

`x+3=12\\ x=9`

Therefore, the answer is:
`9` roses and
`3` lilies.