Machine F takes 7 minutes to cut 77 pieces of lumbers. Machine G takes 17 minutes to cut 119 pieces of lumbers. Machine H takes 13 minutes to cut 169 pieces of lumber.
- Which is the faster combination, F and G or G and H? (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 F alone:
7 min → 77 pieces
1 min → 77 ÷ 7 = 11 pieces
Time taken by Machine G alone:
17 min → 119 pieces
1 min → 119 ÷ 17 = 7 pieces
Time taken by Machine H alone:
13 min → 119 pieces
1 min → 169 ÷ 13 = 13 pieces
Time taken by Machine F and Machine G together:
1 min → 11 + 7 = 18 pieces
Time taken by Machine G and Machine H together:
1 min → 7 + 13 = 20 pieces
Machine G and H are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine G and H) in 1 minute
= 20 - 18
= 2
Answer(s): (a) G, H or H, G; (b) 2