Machine A takes 6 minutes to cut 66 pieces of lumbers. Machine B takes 18 minutes to cut 162 pieces of lumbers. Machine C takes 11 minutes to cut 154 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:
6 min → 66 pieces
1 min → 66 ÷ 6 = 11 pieces
Time taken by Machine B alone:
18 min → 162 pieces
1 min → 162 ÷ 18 = 9 pieces
Time taken by Machine C alone:
11 min → 162 pieces
1 min → 154 ÷ 11 = 14 pieces
Time taken by Machine A and Machine B together:
1 min → 11 + 9 = 20 pieces
Time taken by Machine B and Machine C together:
1 min → 9 + 14 = 23 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
= 23 - 20
= 3
Answer(s): (a) B, C or C, B; (b) 3
