Machine A takes 10 minutes to cut 110 pieces of lumbers. Machine B takes 18 minutes to cut 108 pieces of lumbers. Machine C takes 15 minutes to cut 225 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:
10 min → 110 pieces
1 min → 110 ÷ 10 = 11 pieces
Time taken by Machine B alone:
18 min → 108 pieces
1 min → 108 ÷ 18 = 6 pieces
Time taken by Machine C alone:
15 min → 108 pieces
1 min → 225 ÷ 15 = 15 pieces
Time taken by Machine A and Machine B together:
1 min → 11 + 6 = 17 pieces
Time taken by Machine B and Machine C together:
1 min → 6 + 15 = 21 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
= 21 - 17
= 4
Answer(s): (a) B, C or C, B; (b) 4