Mary lives 2.1 miles north of her school. Her classmate Roger lives 1.3 miles west of their school. What is the distance between Mary and Roger's houses? Round your answer to the nearest tenth of a mile.

The answer is 2.5 miles.

To answer this question, you need to use the Pythagoras theorem, which is: a square + b square = c square.

A is 2.1 miles. 2.1 squared is 4.41.

B is 1.3 miles. 1.3 squared is 1.69.

If you add those two, it becomes 6.1.

The square root of that (you'll need a calculator) is 2.4698 ..., which, rounded to the nearest tenth of a mile is 2.5