Machine B takes 11 minutes to cut 176 pieces of lumbers. Machine C takes 17 minutes to cut 170 pieces of lumbers. Machine D takes 7 minutes to cut 84 pieces of lumber.
- Which is the faster combination, B and C or C and D? (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 B alone:
11 min → 176 pieces
1 min → 176 ÷ 11 = 16 pieces
Time taken by Machine C alone:
17 min → 170 pieces
1 min → 170 ÷ 17 = 10 pieces
Time taken by Machine D alone:
7 min → 170 pieces
1 min → 84 ÷ 7 = 12 pieces
Time taken by Machine B and Machine C together:
1 min → 16 + 10 = 26 pieces
Time taken by Machine C and Machine D together:
1 min → 10 + 12 = 22 pieces
Machine B and C are the faster combination.
(b)
Number of more pieces of lumbers that can be cut by the faster combination (Machine B and C) in 1 minute
= 26 - 22
= 4
Answer(s): (a) B, C or C, B; (b) 4