Machine X takes 9 minutes to cut 99 pieces of lumbers. Machine Y takes 10 minutes to cut 120 pieces of lumbers. Machine Z takes 13 minutes to cut 182 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:
9 min → 99 pieces
1 min → 99 ÷ 9 = 11 pieces
Time taken by Machine Y alone:
10 min → 120 pieces
1 min → 120 ÷ 10 = 12 pieces
Time taken by Machine Z alone:
13 min → 120 pieces
1 min → 182 ÷ 13 = 14 pieces
Time taken by Machine X and Machine Y together:
1 min → 11 + 12 = 23 pieces
Time taken by Machine Y and Machine Z together:
1 min → 12 + 14 = 26 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
= 26 - 23
= 3
Answer(s): (a) Y, Z or Z, Y; (b) 3