Machine X takes 7 minutes to cut 70 pieces of lumbers. Machine Y takes 19 minutes to cut 152 pieces of lumbers. Machine Z takes 14 minutes to cut 168 pieces of lumber.
- Which is the faster combination, X and Y or Y and Z? (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 X alone:
7 min → 70 pieces
1 min → 70 ÷ 7 = 10 pieces
Time taken by Machine Y alone:
19 min → 152 pieces
1 min → 152 ÷ 19 = 8 pieces
Time taken by Machine Z alone:
14 min → 152 pieces
1 min → 168 ÷ 14 = 12 pieces
Time taken by Machine X and Machine Y together:
1 min → 10 + 8 = 18 pieces
Time taken by Machine Y and Machine Z together:
1 min → 8 + 12 = 20 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
= 20 - 18
= 2
Answer(s): (a) Y, Z or Z, Y; (b) 2