Machine X takes 8 minutes to cut 88 pieces of lumbers. Machine Y takes 14 minutes to cut 126 pieces of lumbers. Machine Z takes 9 minutes to cut 135 pieces of lumber. 

1. Which is the faster combination, X and Y or Y and Z? (Eg A, B) 
2. 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 X alone:
8 min → 88 pieces
1 min → 88 ÷ 8 = 11 pieces

Time taken by Machine Y alone:
14 min → 126 pieces
1 min → 126 ÷ 14 = 9 pieces

Time taken by Machine Z alone:
9 min → 126 pieces
1 min → 135 ÷ 9 = 15 pieces

Time taken by Machine X and Machine Y together:
1 min → 11 + 9 = 20 pieces

Time taken by Machine Y and Machine Z together:
1 min → 9 + 15 = 24 pieces

Machine Y and Z are the faster combination.

(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine Y and Z) in 1 minute
= 24 - 20
= 4 

Answer(s): (a) Y, Z or Z, Y; (b) 4