Jingjing's home is 45 degrees southwest of Nini's home.

Yan Yan's home is 45 degrees southeast of Nini's home.

So Jingjing's family and Yanyan's family form an included angle of 90 degrees, and 97 and 100 are two right-angled sides.

So the answer calculated by Pythagorean theorem is divisor ~ ~

139.3m