PSLE A rectangular block R was cut along the dotted line into two smaller rectangular blocks of equal height, S and T, as shown. The volume of T is 12584 cm
3 more than that of S.
- What is the height of each block?
- Harry packed 6 of block T such that they fit exactly into a box with a square base. The box has the same height as T. At most, how many of block S can be packed into such a box?
(a)
Base area of Block S
= 17 x 26
= 442 cm
2 Base area of Block T
= 39 x 26
= 1014 cm
2 Base area of Block T more than Block S
= 1014 - 442
= 572 cm
2 Height of each block
= 12584 ÷ 572
= 22 cm
(b)
Base area of the box
= 6 x 1014
= 6084 cm
3 Length of the box
= √6084
= 78 cm
Number of Block S along the length of the box
= 78 ÷ 17
= 4 r 10
Number of Block S along the breadth of the box
= 78 ÷ 26
= 3
Number of Block S to pack into the box at most
= 4 x 3
= 12
Answer(s): (a) 22 cm; (b) 12