Question

A flight from Dehradun stops at New Delhi and then continues to Jaipur. The flight time from Dehradun to New Delhi is about $ \dfrac{3}{5}\text{ hours} $ and the flight time from New Delhi to Jaipur is about $ \dfrac{4}{5}\text{ hours}\text{.} $ Find the total flight time.

Answer 1

Hint: To find the total time of flight in the journey from Dehradun to Jaipur find the time that is taken from Dehradun and New Delhi and the time taken from New Delhi to Jaipur. For adding the two fractions take the LCM as 5 and solve. Finally, report the answer in fraction as well as decimal form.

Complete step-by-step answer:
It is given that a flight from Dehradun stops at New Delhi and then continues to Jaipur. The flight time from Dehradun to New Delhi is about $ \dfrac{3}{5}\text{ hours} $ and the flight time from New Delhi to Jaipur is about $ \dfrac{4}{5}\text{ hours} $ . We are asked the total time of flight, so for finding the total time of flight add the two times, i.e., the time of flight from Dehradun to New Delhi and the time from New Delhi to Jaipur.
 $ \therefore \text{The total time of flight}=\dfrac{3}{5}+\dfrac{4}{5} $
Now as both the fractions have the same denominator, the LCM of the two denominators is 5.
 $ \therefore \text{The total time of flight}=\dfrac{3+4}{5}=\dfrac{7}{5}\text{ hours} $
So, the answer to the above question is $ \dfrac{7}{5} $ hours, which can be written in the form of decimal as 1.4 hours.

Note: Remember that time of flight and time of journey are two different things. The time for which the plane was flying is the time of flight, while the time of the whole journey, i.e., time of flight added with stoppage time is the time of journey. So, in the above question you are asked the time of flight and not the time of the whole journey.