PSLE A rectangular block A was cut along the dotted line into two smaller rectangular blocks of equal height, B and C, as shown. The volume of C is 9680 cm
3 more than that of B.
- What is the height of each block?
- Ben packed 6 of block C such that they fit exactly into a box with a square base. The box has the same height as C. At most, how many of block B can be packed into such a box?
(a)
Base area of Block B
= 13 x 22
= 286 cm
2 Base area of Block C
= 33 x 22
= 726 cm
2 Base area of Block C more than Block B
= 726 - 286
= 440 cm
2 Height of each block
= 9680 ÷ 440
= 22 cm
(b)
Base area of the box
= 6 x 726
= 4356 cm
3 Length of the box
= √4356
= 66 cm
Number of Block B along the length of the box
= 66 ÷ 13
= 5 r 1
Number of Block B along the breadth of the box
= 66 ÷ 22
= 3
Number of Block B to pack into the box at most
= 5 x 3
= 15
Answer(s): (a) 22 cm; (b) 15