Machine D takes 5 minutes to cut 100 pieces of lumbers. Machine E takes 17 minutes to cut 153 pieces of lumbers. Machine F takes 10 minutes to cut 170 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:
5 min → 100 pieces
1 min → 100 ÷ 5 = 20 pieces
Time taken by Machine E alone:
17 min → 153 pieces
1 min → 153 ÷ 17 = 9 pieces
Time taken by Machine F alone:
10 min → 153 pieces
1 min → 170 ÷ 10 = 17 pieces
Time taken by Machine D and Machine E together:
1 min → 20 + 9 = 29 pieces
Time taken by Machine E and Machine F together:
1 min → 9 + 17 = 26 pieces
Machine D and E are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine D and E) in 1 minute
= 29 - 26
= 3
Answer(s): (a) D, E or E, D; (b) 3