PSLE A rectangular block V was cut along the dotted line into two smaller rectangular blocks of equal height, W and X, as shown. The volume of X is 1350 cm
3 more than that of W.
- What is the height of each block?
- Henry packed 6 of block X such that they fit exactly into a box with a square base. The box has the same height as X. At most, how many of block W can be packed into such a box?
(a)
Base area of Block W
= 6 x 10
= 60 cm
2 Base area of Block X
= 15 x 10
= 150 cm
2 Base area of Block X more than Block W
= 150 - 60
= 90 cm
2 Height of each block
= 1350 ÷ 90
= 15 cm
(b)
Base area of the box
= 6 x 150
= 900 cm
3 Length of the box
= √900
= 30 cm
Number of Block W along the length of the box
= 30 ÷ 6
= 5 r 0
Number of Block W along the breadth of the box
= 30 ÷ 10
= 3
Number of Block W to pack into the box at most
= 5 x 3
= 15
Answer(s): (a) 15 cm; (b) 15