Craig grades 999 tests every 222222 minutes.

If Craig has 636363 tests to grade, how long will it take him?

So what you want to do is divide 222222/999 to get how many minutes is takes for one test.

222222/999=222.444 ...

Then multiply 636363 to 222.444 ...

It will equal 141555414

So it takes Craig 141555414 minutes to complete 636363 test

All you have to do is

222222 / 999 = 222.44

222.44 x 636363 = 141555414

There's your answer!