Question

Two calendar dates are 180 days apart. If the first date is on a Tuesday, on what day of the week is the second date?

Answer 1

If today is tuesday, then in 7 days from now it is tuesday, from 14 days from now it is Tuesday, from 21 days from now it is tuesday, etc.
So first you can divide 180 by 7.

You can also approach this using modular math.

Answer 2

or clock arithmetic