A person travels from P to Q a speed of 80 km/hr and returns by increasing his speed by 10%.

A person travels from P to Q a speed of 80 km/hr and returns by increasing his speed by 10%. What is his average speed for both the trips?

Answer/Solution

84

Steps/Work

Speed on return trip = 110% of 80 = 88 km/hr.
Average speed of trip = 80 + 88 /2 = 168/2 = 84 km/hr
Answer : D

General Calculator / Auto Solver

A person travels from p to q a speed of km / hr and returns by increasing his speed by %. What is his average speed for both the trips?

Calculated Answer

84

Step by Step Solution

In order to solve problem, you must evaluate (n₀ + n₀ * (n₁ / 100 + 1)) / 2.

n₀ =	80
n₁ =	10

(n₀ + n₀ * (n₁ / 100 + 1)) / 2
Evaluate n₁ / 100 = 0.1
(n₀ + n₀ * (0.1 + 1)) / 2
Evaluate 0.1 + 1 = 1.1
(n₀ + n₀ * 1.1) / 2
Evaluate n₀ * 1.1 = 88
(n₀ + 88) / 2
Evaluate n₀ + 88 = 168
168 / 2
Evaluate 168 / 2 = 84
84
The answer to the problem and the result of (n₀ + n₀ * (n₁ / 100 + 1)) / 2 is 84