Question

Lucy bought a doormat for $7 and some placemats for $2 each. Her total average cost per item was $3. Create a rational equation, and determine how many placemats she bought.

Answer 1

4

Explanation:

is the answer

Answer 2

Lucy bought 4 placemats.

Explanation:

Let n be the number of placemats Lucy bought.

1 doormat = $7

1 placemat = $2

n placemats = $2n

Total = $(7+2n)

Total number of objects bought = n+1

Average
`=(\$(7+2n))/(n+1)`

So,

`(\$(7+2n))/(n+1)=\$3`

Solve this equation:

`7+2n=3(n+1)\\ \\7+2n=3n+3\\ \\3n-2n=7-3\\ \\n=4`

Hence, Lucy bought 4 placemats.