Home » A car travels from calabar to Enugu, a distance of P km with an average…

A car travels from calabar to Enugu, a distance of P km with an average…

A car travels from calabar to Enugu, a distance of P km with an average speed of U km per hour and continues to benin, a distance of Q km, with an average speed of Wkm per hour. Find its average speed from Calabar to Benin
  • A.
    (frac{(p + q)}{pw + qu})
  • B.
    (frac{uw(p + q)}{pw + qu})
  • C.
    (frac{uw(p + q)}{pw})
  • D.
    (frac{uw}{pw + qu})
Correct Answer: Option B
Explanation

Average speed = (frac{text{total Distance}}{text{Total Time})
from Calabar to Enugu in time t1, hence
t1 = (frac{P}{U}) also from Enugu to Benin
t2 (frac{q}{w})
Av. speed = (frac{p + q}{t_1 + t_2}
= (frac{p + q}{frac{p}{u} + frac{q}{w})
= p + q x (frac{uw}{pw + qu})
= (frac{uw(p + q)}{pw + qu})