Machine A takes 8 minutes to cut 88 pieces of lumbers. Machine B takes 14 minutes to cut 168 pieces of lumbers. Machine C takes 9 minutes to cut 135 pieces of lumber.
- Which is the faster combination, A and B or B and C? (Eg A, B)
- In 1 minute, how many more pieces of lumbers can be cut by the faster combination compared to the other combination?
(a)
Time taken by Machine A alone:
8 min → 88 pieces
1 min → 88 ÷ 8 = 11 pieces
Time taken by Machine B alone:
14 min → 168 pieces
1 min → 168 ÷ 14 = 12 pieces
Time taken by Machine C alone:
9 min → 168 pieces
1 min → 135 ÷ 9 = 15 pieces
Time taken by Machine A and Machine B together:
1 min → 11 + 12 = 23 pieces
Time taken by Machine B and Machine C together:
1 min → 12 + 15 = 27 pieces
Machine B and C are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine B and C) in 1 minute
= 27 - 23
= 4
Answer(s): (a) B, C or C, B; (b) 4