Kim uses decals to decorate 6 cars and 3 mopeds. She used ¾ of the decals on the cars and ¼ of the remaining decals on the mopeds. She has 9 decals leftover. How many decals did she use on each car?

Kim used 6 decals on each car

Step-by-step explanation:

1. Let's review all the information given to answer the question:

Number of card Kim decorated = 6

Number of mopeds Kim decorated = 3

Decals used on the cars = 3/4

Decals used on the mopeds = 1/4 of the remaining

Decals remaining = 9

2. Let's calculate how many decals Kim used on cars:

x = Number of decals before starting to decorate

x - 3x/4 - 1/4 (x - 3x/4) = 9

x - 3x/4 - x/4 + 3x/16 = 9

16x - 12x - 4x + 3x = 144 (16 as Lowest common denominator)

3x = 144

x = 48 (Dividing b y 3)

Kim had 48 decals before starting to decorate

3/4x = 36

3/4 * 48 = 36

Kim used 36 decals to decorate the cars

36/6 = 6

Kim used 6 decals on each car