PSLE A rectangular block R was cut along the dotted line into two smaller rectangular blocks of equal height, S and T, as shown. The volume of T is 140 cm
3 more than that of S.
- What is the height of each block?
- Riordan packed 6 of block T such that they fit exactly into a box with a square base. The box has the same height as T. At most, how many of block S can be packed into such a box?
(a)
Base area of Block S
= 1 x 4
= 4 cm
2 Base area of Block T
= 6 x 4
= 24 cm
2 Base area of Block T more than Block S
= 24 - 4
= 20 cm
2 Height of each block
= 140 ÷ 20
= 7 cm
(b)
Base area of the box
= 6 x 24
= 144 cm
3 Length of the box
= √144
= 12 cm
Number of Block S along the length of the box
= 12 ÷ 1
= 12 r 0
Number of Block S along the breadth of the box
= 12 ÷ 4
= 3
Number of Block S to pack into the box at most
= 12 x 3
= 36
Answer(s): (a) 7 cm; (b) 36