Machine C takes 10 minutes to cut 190 pieces of lumbers. Machine D takes 12 minutes to cut 96 pieces of lumbers. Machine E takes 9 minutes to cut 108 pieces of lumber.
- Which is the faster combination, C and D or D and E? (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 C alone:
10 min → 190 pieces
1 min → 190 ÷ 10 = 19 pieces
Time taken by Machine D alone:
12 min → 96 pieces
1 min → 96 ÷ 12 = 8 pieces
Time taken by Machine E alone:
9 min → 96 pieces
1 min → 108 ÷ 9 = 12 pieces
Time taken by Machine C and Machine D together:
1 min → 19 + 8 = 27 pieces
Time taken by Machine D and Machine E together:
1 min → 8 + 12 = 20 pieces
Machine C and D are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine C and D) in 1 minute
= 27 - 20
= 7
Answer(s): (a) C, D or D, C; (b) 7
