Machine E takes 9 minutes to cut 90 pieces of lumbers. Machine F takes 10 minutes to cut 60 pieces of lumbers. Machine G takes 15 minutes to cut 225 pieces of lumber.
- Which is the faster combination, E and F or F and G? (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 E alone:
9 min → 90 pieces
1 min → 90 ÷ 9 = 10 pieces
Time taken by Machine F alone:
10 min → 60 pieces
1 min → 60 ÷ 10 = 6 pieces
Time taken by Machine G alone:
15 min → 60 pieces
1 min → 225 ÷ 15 = 15 pieces
Time taken by Machine E and Machine F together:
1 min → 10 + 6 = 16 pieces
Time taken by Machine F and Machine G together:
1 min → 6 + 15 = 21 pieces
Machine F and G are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine F and G) in 1 minute
= 21 - 16
= 5
Answer(s): (a) F, G or G, F; (b) 5