The figure is not drawn to scale. It shows the net of a solid. It is made up of 4 identical rectangles and 2 identical squares. Line D is 40 cm long and Line E is 15 cm long.
- Find the volume of the solid.
- This solid is a cardboard carton containing small boxes of mini cupcakes. Each box of mini cupcakes is 3 cm by 2 cm by 1 cm. If all these small boxes of mini cupcakes in the carton occupy more than 60% of the carton's volume, what is the minimum number of small boxes of mini cupcakes in the carton?
(a)
Breadth of the cuboid
= 15 ÷ 3
= 5 cm
Breadth of two squares
= Breadth x 2
= 5 x 2
= 10 cm
Length of the cuboid
= (40 - 10) ÷ 2
= 15 cm
Volume of the cuboid
= 15 x 5 x 5
= 375 cm
3 (b)
Volume of one box of mini cupcakes
= 3 x 2 x 1
= 6 cm
3 Volume of space occupied
= 375 x 60%
= 225 cm
3 Estimated number of small boxes
= 225 ÷ 6
≈ 37.5
Minimum number of small boxes to occupy more than 60% of the carton
= 37 + 1
= 38
Answer(s): (a) 375 cm
3; (b) 38