Question

A bread making machine can make bread of 50 kg dough in 3 minutes. how many such machines are required to make breads of 300 kg dough in 6 minutes?

Answer 1

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Answer 2

1 machine : 50 kg : 3 mins

Find the number of machines to make 300 kg in 3 mins:

300 ÷ 50 = 6 ⇒ the multiplier is 6

Number of machines varies directly with the  amount of dough

1 x 6 machines : 50 x 6 kg : 3 mins

6 machines : 300 kg : 3 mins

Find the number of machines needed if the 300 kg dough is done in 6 mins:

6 ÷ 3 = 2 ⇒ the multiplier is 2

The number of machine is inversely proportional to to the time needed.

6 ÷ 2 machines : 300 kg : 3 x 2 mins

3 machines : 300 kg : 6 mins

Answer: We will need 3 machines.