Name: Tom

Who is asking: Teacher
Level: Secondary

Two students have to type a project. One can do it in 2 hours. It would take the other student three hours. They have 2 type writers. How fast can they finish by working simultaneously?

Hi Tom,

It will take them at least 1 hour and 12 minutes: In 6 hours, the first student could type 3 copies of the project, and the second student 2. So they could type a total of 5 copies of the project in 6 hours. For just one copy, they need one fifth of that time, that is, 1 hour and 12 minutes.

Of course, this assumes idealized conditions where they can split the work however they want: The first student will be typing 3 fifths of the work and the second 2 fifths, so they need to be able to divide the chapters into parts representing respectively 3 fifths and 2 fifths of the typing.

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