Machine Z takes 7 minutes to cut 70 pieces of lumbers. Machine A takes 10 minutes to cut 70 pieces of lumbers. Machine B takes 11 minutes to cut 132 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:
7 min → 70 pieces
1 min → 70 ÷ 7 = 10 pieces
Time taken by Machine A alone:
10 min → 70 pieces
1 min → 70 ÷ 10 = 7 pieces
Time taken by Machine B alone:
11 min → 70 pieces
1 min → 132 ÷ 11 = 12 pieces
Time taken by Machine Z and Machine A together:
1 min → 10 + 7 = 17 pieces
Time taken by Machine A and Machine B together:
1 min → 7 + 12 = 19 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
= 19 - 17
= 2
Answer(s): (a) A, B or B, A; (b) 2