Machine Y takes 7 minutes to cut 91 pieces of lumbers. Machine Z takes 11 minutes to cut 121 pieces of lumbers. Machine A takes 9 minutes to cut 135 pieces of lumber.
- Which is the faster combination, Y and Z or Z and A? (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 Y alone:
7 min → 91 pieces
1 min → 91 ÷ 7 = 13 pieces
Time taken by Machine Z alone:
11 min → 121 pieces
1 min → 121 ÷ 11 = 11 pieces
Time taken by Machine A alone:
9 min → 121 pieces
1 min → 135 ÷ 9 = 15 pieces
Time taken by Machine Y and Machine Z together:
1 min → 13 + 11 = 24 pieces
Time taken by Machine Z and Machine A together:
1 min → 11 + 15 = 26 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