PSLE A rectangular block B was cut along the dotted line into two smaller rectangular blocks of equal height, C and D, as shown. The volume of D is 8400 cm
3 more than that of C.
- What is the height of each block?
- Howard packed 6 of block D such that they fit exactly into a box with a square base. The box has the same height as D. At most, how many of block C can be packed into such a box?
(a)
Base area of Block C
= 11 x 24
= 264 cm
2 Base area of Block D
= 36 x 24
= 864 cm
2 Base area of Block D more than Block C
= 864 - 264
= 600 cm
2 Height of each block
= 8400 ÷ 600
= 14 cm
(b)
Base area of the box
= 6 x 864
= 5184 cm
3 Length of the box
= √5184
= 72 cm
Number of Block C along the length of the box
= 72 ÷ 11
= 6 r 6
Number of Block C along the breadth of the box
= 72 ÷ 24
= 3
Number of Block C to pack into the box at most
= 6 x 3
= 18
Answer(s): (a) 14 cm; (b) 18