Machine Z takes 9 minutes to cut 171 pieces of lumbers. Machine A takes 15 minutes to cut 105 pieces of lumbers. Machine B takes 8 minutes to cut 136 pieces of lumber.
- Which is the faster combination, Z and A or A and B? (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 Z alone:
9 min → 171 pieces
1 min → 171 ÷ 9 = 19 pieces
Time taken by Machine A alone:
15 min → 105 pieces
1 min → 105 ÷ 15 = 7 pieces
Time taken by Machine B alone:
8 min → 105 pieces
1 min → 136 ÷ 8 = 17 pieces
Time taken by Machine Z and Machine A together:
1 min → 19 + 7 = 26 pieces
Time taken by Machine A and Machine B together:
1 min → 7 + 17 = 24 pieces
Machine Z and A are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine Z and A) in 1 minute
= 26 - 24
= 2
Answer(s): (a) Z, A or A, Z; (b) 2