Question

Keep gettin the wrong answer please help

Answer 1

Nancy bought 12 candy bars.

Explanation:

Let us use the variable
`b` for a candy bar and
`m` for bags of trail mix.

From this paragraph, we can create a system of equations

The first is regarding the price of each.

"A candy bar costs 90 cents" will be
`.9b`

"A bag of trail mix costs 50 cents" will be
`.5m`

"Nancy spent $13.30" will be
`=13.30`

When put all together, the first equation will be
`.9b+.5m=13.3`

"Nancy bought 7 more candy bars than bags of trail mix" will be
`b=m+7`

In order to find how many candy bars that Nancy bought, we need to solve this system of equation.

To solve this system of equations, we can use the substitution method by replacing the
`b` in the first equation with
`m+7`

`.9(m+7)+.5m=13.3`

Now, we can solve for
`m`

`.9(m+7)+.5m=13.3\\\\.9m+6.3+.5m=13.3\\\\1.4m+6.3=13.3\\\\1.4m=7\\\\m=(7)/(1.4) \\\\m=5`

Now that we know how many bags of trail mix were bought, we can use the second equation to find how many candy bars were bought

`b=m+7\\\\b=5+7\\\\b=12`

While we have the answer, it is good practice to check that this answer is correct. To do this, we can substitute in the values for
`b` and
`m` into the first equation

`.9(12)+.5(5)=13.3\\\\10.8+2.5=13.3\\\\13.3=13.3`