PSLE A rectangular block Q was cut along the dotted line into two smaller rectangular blocks of equal height, R and S, as shown. The volume of S is 336 cm
3 more than that of R.
- What is the height of each block?
- George packed 8 of block S such that they fit exactly into a box with a square base. The box has the same height as S. At most, how many of block R can be packed into such a box?
(a)
Base area of Block R
= 3 x 8
= 24 cm
2 Base area of Block S
= 12 x 8
= 72 cm
2 Base area of Block S more than Block R
= 72 - 24
= 48 cm
2 Height of each block
= 336 ÷ 48
= 7 cm
(b)
Base area of the box
= 8 x 72
= 576 cm
3 Length of the box
= √576
= 24 cm
Number of Block R along the length of the box
= 24 ÷ 3
= 8 r 0
Number of Block R along the breadth of the box
= 24 ÷ 8
= 3
Number of Block R to pack into the box at most
= 8 x 3
= 24
Answer(s): (a) 7 cm; (b) 24