Machine D takes 7 minutes to cut 70 pieces of lumbers. Machine E takes 13 minutes to cut 117 pieces of lumbers. Machine F takes 10 minutes to cut 150 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:
7 min → 70 pieces
1 min → 70 ÷ 7 = 10 pieces
Time taken by Machine E alone:
13 min → 117 pieces
1 min → 117 ÷ 13 = 9 pieces
Time taken by Machine F alone:
10 min → 117 pieces
1 min → 150 ÷ 10 = 15 pieces
Time taken by Machine D and Machine E together:
1 min → 10 + 9 = 19 pieces
Time taken by Machine E and Machine F together:
1 min → 9 + 15 = 24 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
= 24 - 19
= 5
Answer(s): (a) E, F or F, E; (b) 5