Machine X takes 5 minutes to cut 85 pieces of lumbers. Machine Y takes 10 minutes to cut 70 pieces of lumbers. Machine Z takes 11 minutes to cut 143 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:
5 min → 85 pieces
1 min → 85 ÷ 5 = 17 pieces
Time taken by Machine Y alone:
10 min → 70 pieces
1 min → 70 ÷ 10 = 7 pieces
Time taken by Machine Z alone:
11 min → 70 pieces
1 min → 143 ÷ 11 = 13 pieces
Time taken by Machine X and Machine Y together:
1 min → 17 + 7 = 24 pieces
Time taken by Machine Y and Machine Z together:
1 min → 7 + 13 = 20 pieces
Machine X and Y are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine X and Y) in 1 minute
= 24 - 20
= 4
Answer(s): (a) X, Y or Y, X; (b) 4