PSLE A rectangular block M was cut along the dotted line into two smaller rectangular blocks of equal height, N and P, as shown. The volume of P is 7600 cm
3 more than that of N.
- What is the height of each block?
- John packed 6 of block P such that they fit exactly into a box with a square base. The box has the same height as P. At most, how many of block N can be packed into such a box?
(a)
Base area of Block N
= 10 x 20
= 200 cm
2 Base area of Block P
= 30 x 20
= 600 cm
2 Base area of Block P more than Block N
= 600 - 200
= 400 cm
2 Height of each block
= 7600 ÷ 400
= 19 cm
(b)
Base area of the box
= 6 x 600
= 3600 cm
3 Length of the box
= √3600
= 60 cm
Number of Block N along the length of the box
= 60 ÷ 10
= 6 r 0
Number of Block N along the breadth of the box
= 60 ÷ 20
= 3
Number of Block N to pack into the box at most
= 6 x 3
= 18
Answer(s): (a) 19 cm; (b) 18