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 98 cm
3 more than that of R.
- What is the height of each block?
- Lee 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
= 1 x 4
= 4 cm
2 Base area of Block S
= 6 x 4
= 18 cm
2 Base area of Block S more than Block R
= 18 - 4
= 14 cm
2 Height of each block
= 98 ÷ 14
= 7 cm
(b)
Base area of the box
= 8 x 18
= 144 cm
3 Length of the box
= √144
= 12 cm
Number of Block R along the length of the box
= 12 ÷ 1
= 12 r 0
Number of Block R along the breadth of the box
= 12 ÷ 4
= 3
Number of Block R to pack into the box at most
= 12 x 3
= 36
Answer(s): (a) 7 cm; (b) 36