You can ride your bike around your block twice and the whole neighborhood once in 10 minutes. You can ride your bike around your block twice and the whole neighborhood 4 times in 31 minutes. How long does it take you to ride around the neighborhood?

Answer 1

both times include two blocks, so the only difference is the neighborhood laps.
3n = 31-10

Answer 2

You have to solve it

Answer 3

The answer is 7