Question

Han and Clare are stuffing envelopes. Han can stuff 20 envelopes in one minute, and Clare can stuff 10 envelopes in one minute. They start working together on a pile of 1,000 envelopes. How long does it take them to finish the pile?

Answer 1

it will take them 33 minutes and 20 seconds

Explanation:

What we have here is that Han can stuff 20 envelopes in a minute while Clare can do 10 in a minute

So in a minute, they can jointly stuff 30 envelopes.

Mathematically we know that the number of time it will take to finish stuffing would be number of envelopes/ joint rate = 1000/30 envelopes per minute

So it will take 33 1/3 minutes

1/3 of a minute is same as 1/3 * 60 seconds = 20 seconds

So it will take them 33 minutes and 20 seconds