Machine Z takes 5 minutes to cut 50 pieces of lumbers. Machine A takes 20 minutes to cut 240 pieces of lumbers. Machine B takes 11 minutes to cut 165 pieces of lumber.
- Which is the faster combination, Z and A or A and B? (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 Z alone:
5 min → 50 pieces
1 min → 50 ÷ 5 = 10 pieces
Time taken by Machine A alone:
20 min → 240 pieces
1 min → 240 ÷ 20 = 12 pieces
Time taken by Machine B alone:
11 min → 240 pieces
1 min → 165 ÷ 11 = 15 pieces
Time taken by Machine Z and Machine A together:
1 min → 10 + 12 = 22 pieces
Time taken by Machine A and Machine B together:
1 min → 12 + 15 = 27 pieces
Machine A and B are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine A and B) in 1 minute
= 27 - 22
= 5
Answer(s): (a) A, B or B, A; (b) 5