Question

A stamping machine can stamp 40 envelopes in 8 minutes. How many of stamping machines, working at the same time, are required to stamp 120 envelopes per minute?

Answer 1

Resposta:

24 stamping machines.

Explicação passo a passo:

Look that if a single stamping machine can stamp 40 envelopes in 8 minutes, it can stamp $\frac{40}{8} = 5$ envelopes per minute. So, to stamp 120 envelopes per minute we need $\frac{120}{5} = 24$ stamping machines.