Machine S takes 9 minutes to cut 90 pieces of lumbers. Machine T takes 17 minutes to cut 102 pieces of lumbers. Machine U takes 10 minutes to cut 150 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:
9 min → 90 pieces
1 min → 90 ÷ 9 = 10 pieces
Time taken by Machine T alone:
17 min → 102 pieces
1 min → 102 ÷ 17 = 6 pieces
Time taken by Machine U alone:
10 min → 102 pieces
1 min → 150 ÷ 10 = 15 pieces
Time taken by Machine S and Machine T together:
1 min → 10 + 6 = 16 pieces
Time taken by Machine T and Machine U together:
1 min → 6 + 15 = 21 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
= 21 - 16
= 5
Answer(s): (a) T, U or U, T; (b) 5