Machine H takes 10 minutes to cut 160 pieces of lumbers. Machine J takes 20 minutes to cut 160 pieces of lumbers. Machine K takes 9 minutes to cut 108 pieces of lumber.
- Which is the faster combination, H and J or J and K? (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 H alone:
10 min → 160 pieces
1 min → 160 ÷ 10 = 16 pieces
Time taken by Machine J alone:
20 min → 160 pieces
1 min → 160 ÷ 20 = 8 pieces
Time taken by Machine K alone:
9 min → 160 pieces
1 min → 108 ÷ 9 = 12 pieces
Time taken by Machine H and Machine J together:
1 min → 16 + 8 = 24 pieces
Time taken by Machine J and Machine K together:
1 min → 8 + 12 = 20 pieces
Machine H and J are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine H and J) in 1 minute
= 24 - 20
= 4
Answer(s): (a) H, J or J, H; (b) 4