Machine P takes 7 minutes to cut 70 pieces of lumbers. Machine Q takes 14 minutes to cut 154 pieces of lumbers. Machine R takes 8 minutes to cut 96 pieces of lumber.
- Which is the faster combination, P and Q or Q and R? (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 P alone:
7 min → 70 pieces
1 min → 70 ÷ 7 = 10 pieces
Time taken by Machine Q alone:
14 min → 154 pieces
1 min → 154 ÷ 14 = 11 pieces
Time taken by Machine R alone:
8 min → 154 pieces
1 min → 96 ÷ 8 = 12 pieces
Time taken by Machine P and Machine Q together:
1 min → 10 + 11 = 21 pieces
Time taken by Machine Q and Machine R together:
1 min → 11 + 12 = 23 pieces
Machine Q and R are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine Q and R) in 1 minute
= 23 - 21
= 2
Answer(s): (a) Q, R or R, Q; (b) 2