Machine D takes 8 minutes to cut 88 pieces of lumbers. Machine E takes 20 minutes to cut 180 pieces of lumbers. Machine F takes 9 minutes to cut 126 pieces of lumber.
- Which is the faster combination, D and E or E and F? (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 D alone:
8 min → 88 pieces
1 min → 88 ÷ 8 = 11 pieces
Time taken by Machine E alone:
20 min → 180 pieces
1 min → 180 ÷ 20 = 9 pieces
Time taken by Machine F alone:
9 min → 180 pieces
1 min → 126 ÷ 9 = 14 pieces
Time taken by Machine D and Machine E together:
1 min → 11 + 9 = 20 pieces
Time taken by Machine E and Machine F together:
1 min → 9 + 14 = 23 pieces
Machine E and F are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine E and F) in 1 minute
= 23 - 20
= 3
Answer(s): (a) E, F or F, E; (b) 3