PSLE A rectangular block T was cut along the dotted line into two smaller rectangular blocks of equal height, U and V, as shown. The volume of V is 5520 cm
3 more than that of U.
- What is the height of each block?
- Glen packed 8 of block V such that they fit exactly into a box with a square base. The box has the same height as V. At most, how many of block U can be packed into such a box?
(a)
Base area of Block U
= 17 x 24
= 408 cm
2 Base area of Block V
= 36 x 24
= 648 cm
2 Base area of Block V more than Block U
= 648 - 408
= 240 cm
2 Height of each block
= 5520 ÷ 240
= 23 cm
(b)
Base area of the box
= 8 x 648
= 5184 cm
3 Length of the box
= √5184
= 72 cm
Number of Block U along the length of the box
= 72 ÷ 17
= 4 r 4
Number of Block U along the breadth of the box
= 72 ÷ 24
= 3
Number of Block U to pack into the box at most
= 4 x 3
= 12
Answer(s): (a) 23 cm; (b) 12