Machine H takes 6 minutes to cut 120 pieces of lumbers. Machine J takes 16 minutes to cut 128 pieces of lumbers. Machine K takes 11 minutes to cut 154 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:
6 min → 120 pieces
1 min → 120 ÷ 6 = 20 pieces
Time taken by Machine J alone:
16 min → 128 pieces
1 min → 128 ÷ 16 = 8 pieces
Time taken by Machine K alone:
11 min → 128 pieces
1 min → 154 ÷ 11 = 14 pieces
Time taken by Machine H and Machine J together:
1 min → 20 + 8 = 28 pieces
Time taken by Machine J and Machine K together:
1 min → 8 + 14 = 22 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
= 28 - 22
= 6
Answer(s): (a) H, J or J, H; (b) 6