Machine S takes 10 minutes to cut 110 pieces of lumbers. Machine T takes 11 minutes to cut 121 pieces of lumbers. Machine U takes 12 minutes to cut 168 pieces of lumber.
- Which is the faster combination, S and T or T and U? (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 S alone:
10 min → 110 pieces
1 min → 110 ÷ 10 = 11 pieces
Time taken by Machine T alone:
11 min → 121 pieces
1 min → 121 ÷ 11 = 11 pieces
Time taken by Machine U alone:
12 min → 121 pieces
1 min → 168 ÷ 12 = 14 pieces
Time taken by Machine S and Machine T together:
1 min → 11 + 11 = 22 pieces
Time taken by Machine T and Machine U together:
1 min → 11 + 14 = 25 pieces
Machine T and U are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine T and U) in 1 minute
= 25 - 22
= 3
Answer(s): (a) T, U or U, T; (b) 3