PSLESix identical rectangular boxes can be stacked into a cupboard 1.4 m wide. Two arrangements are shown. The first arrangement in Figure A leaves a 40 cm gap at the top. The second one in Figure B leaves a 12 cm gap at the top and another gap at the side.
- In the arrangement shown in Figure B, what is the width of the gap at the side in m?
- What is the height of the cupboard in metres?
(a)
Cupboard width = 1.4 m
1 m = 100 cm
1.4 m = 140 cm
Width of one rectangle box
= 140 ÷ 2
= 70 cm
Length of the box = 1 u
Height of Figure A = 3 u + 40
Height of Figure B = 1 u + 4 x 70 + 12
The height of Figure A is equal to the height of Figure B.
3 u + 40 = 1 u + 4 x 70 + 12
2 u + 40 = 292
2 u = 292 - 40
2 u = 252
1 u = 252 ÷ 2 = 126
Width of the gap at the side of the cupboard
= 140 - 126
= 14 cm
= 0.14 m
(b)
Height of the cupboard
= 3 x 126 + 40
= 378 + 40
= 418 cm
= 4.18 m
Answer(s): (a) 0.14 m; (b) 4.18 m