Kinley bought 3 notebooks that cost the same and a poster that cost $6. She spent $20.40 in all. What was the cost of each notebook?

the cost of each notebook is $4.8

Step-by-step explanation:

Cost of each notebook=?

Cost of a poster = $6

Total amount she spent = $20.40

If we subtract the cost of poster from total amount we get the cost of 3 notebooks.

$20.40-$6

=$ 14.4

It means the cost of 3 notebooks = $14.4

To find the cost of each notebook divide the cost of 3 notebooks by the number of books.

=14.4/3

=$4.8

Thus the cost of each notebook is $4.8 ...