Math problem...of the 36 cars in a parking lot, 6 are red compact cars, 5 .......?

Question

Of the 36 cars in a parking lot, 6 are red compact cars, 5 are red 2 door cars and 7 are 2-door compacts. Half are not red, 13 are compacts, 20 have 4 doors, and 2 of the compact 4-door cars are not red. How many of the red 4-door cars in the parking lot are not compacts?
This is a homework problem and i can't get it. IF you can please describe how you got the answer. Thank You!

Answer 1

Wow yuck! Not sure I can get this but maybe somebody can continue the work.
(codes: R= Red, NR = not Red, comp = compact, 2d = 2 door
4d= 4 door)

From the problem you get
36cars 6 R comp 5 R 2D 7 2D comp 1/2 NR
13 comp 20 4D 2 of the 4D comp are NR

All cars: 36 cars, 7 2d Comp, 20 4d, 13 comp

Red Cars: 6 R Comp, 5 R 2D

Not Red: 1/2 NR

Ok fun and games time,
1/2 NR =36/2 = 18 NR (all others must be red 36-18 = 18)
13 comp - 6 R comp = 7NR comp

**assuming** that all cars have either 2 or 4 doors?
36 -20 4D = 16 2D 16 2D - 5 R 2d = 11 NR 2D
18NR - 11 NR 2D = 7 NR 4D
20 4D - 7 NR 4D = 13 R 4D

13 comp - 7 2D comp = 6 4D Comp
2 of which are NR 6-2 = *****4 4d R Comp!****

Much easier method
13 comp - 7 2d comp = 6 4d comp
6 4d comp - 2 NR 4d comp = 4 R 4d comp

all that other information is not needed?!