Question

A pencil costs $0.27 and a pen costs $0.32. You buy six pencils and the total cost is $4.18. How many pens did you buy?

Answer 1

`8` pens.

Explanation:

Let's model our situation with an equation.

We're going to have two variables, one for pencils and one for pens.

Let `p` stand for the number of pencils bought, `n` stand for the number of pens bought, and `C` be the total cost (in dollars):

`C=0.27p+0.32n`, as we're given the individual costs of pencils and pens.

We are given our cost, `C=$4.18`. Now, we're also told we buy `6` pencils, so `p=6.` Plug these into our equation:

`4.18=0.27(6)+0.32n`

What we're really being asked is to solve for `n,` so let's do that.

`4.18=1.62+0.32n`

`0.32n=4.18-1.62=2.56`

`n=2.56/0.32=8`

So, we bought `8` pens.

Answer 2

8 pens

Explanation:

say i bought `x` pencils and `y` pens
so `x` pencils cost `0.27 *x` dollars
similarly , `y` pens cost `0.32 * y` dollars

total cost = cost of x pencils +cost of y pens
4.18 = `0.27 * 6` + `0.32*y`
so `y = (4.18 -1.62)/0.32 =8`

so i bought 8 pens