PSLE A rectangular block S was cut along the dotted line into two smaller rectangular blocks of equal height, T and U, as shown. The volume of U is 396 cm
3 more than that of T.
- What is the height of each block?
- Harry packed 6 of block U such that they fit exactly into a box with a square base. The box has the same height as U. At most, how many of block T can be packed into such a box?
(a)
Base area of Block T
= 3 x 6
= 18 cm
2 Base area of Block U
= 9 x 6
= 54 cm
2 Base area of Block U more than Block T
= 54 - 18
= 36 cm
2 Height of each block
= 396 ÷ 36
= 11 cm
(b)
Base area of the box
= 6 x 54
= 324 cm
3 Length of the box
= √324
= 18 cm
Number of Block T along the length of the box
= 18 ÷ 3
= 6 r 0
Number of Block T along the breadth of the box
= 18 ÷ 6
= 3
Number of Block T to pack into the box at most
= 6 x 3
= 18
Answer(s): (a) 11 cm; (b) 18