a man covers a distance of 180 km at 72 kmph and next 190 km at 88 kmph . what is his average speed for his whole journey of 370 km ?
formula = 2 * f . s * s . p / f . s + s . p = 2 * 72 * 88 / 88 + 72 = 79.2 kmph option ' c '
divide(370, add(divide(180, 72), divide(190, 88)))