Adam has some paint.
He uses
78 of it to paint 9 cupboards and 4 doors.
The amount of paint needed to paint a door is 3 times that of a cupboard.
- How many cupboards can he paint using the remaining paint?
- How many doors can he paint using the remaining paint?
|
Cupboards |
Doors |
Number |
9 |
4 |
Value |
1 u |
3 u |
Total value |
9 u |
12 u |
(a)
Paint needed for 1 cupboard = 1 u
Paint needed for 1 door = 3 u
Paint needed for 9 cupboards and 4 doors
= 9 x 1 u x 4 x 3 u
= 9 u + 12 u
= 21 u
78 of the paint = 21 u
18 of the paint = 21 u ÷ 7 = 3 u
Fraction of the remaining paint left
= 1 -
78=
18 18 of the paint = 1 x 3 u = 3 u
Remaining paint left = 3 u
Number of cupboards that Adam can paint with the remaining paint
= 3 u ÷ 1 u
= 3
(b)
Number of doors that Adam can paint with the remaining paint
= 3 u ÷ 3 u
= 1
Answer(s): (a) 3; (b) 1