Question 73
A girl goes from M to N at a speed of 25 km/h and returns to M at a speed of 37.5 km/h, via the same route. What is the girl's average speed (in km/h)?
Solution
average speed = $$\frac{2\times\ speed\ while\ going\times\ speed\ while\ returning}{speed\ while\ going\ +\ speed\ while\ returning}$$
= $$\frac{2\times\ 25\times\ 37.5}{25+37.5}$$
= $$\frac{2\times\ 25\times\ 37.5}{62.5}$$
= $$2\times15$$
= 30 km/h
Get AI Help
Create a FREE account and get:
- Free SSC Study Material - 18000 Questions
- 230+ SSC previous papers with solutions PDF
- 100+ SSC Online Tests for Free
