Machine Y takes 6 minutes to cut 120 pieces of lumbers. Machine Z takes 10 minutes to cut 120 pieces of lumbers. Machine A takes 11 minutes to cut 121 pieces of lumber.
- Which is the faster combination, Y and Z or Z and A? (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 Y alone:
6 min → 120 pieces
1 min → 120 ÷ 6 = 20 pieces
Time taken by Machine Z alone:
10 min → 120 pieces
1 min → 120 ÷ 10 = 12 pieces
Time taken by Machine A alone:
11 min → 120 pieces
1 min → 121 ÷ 11 = 11 pieces
Time taken by Machine Y and Machine Z together:
1 min → 20 + 12 = 32 pieces
Time taken by Machine Z and Machine A together:
1 min → 12 + 11 = 23 pieces
Machine Y and Z are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine Y and Z) in 1 minute
= 32 - 23
= 9
Answer(s): (a) Y, Z or Z, Y; (b) 9