Aptitude - Time and Distance - Discussion

For the first 160km time taken is t = d/s t = 160/64 = 2.5hr,
For the second 160km, the time taken is t=d/s t=160/80 = 2hr.
Average speed = total distance/total time taken.
= 160+160/2.5+2.
= 320/4.5.
= 71.11 km/hr.

@All.

Start 1st half 160/64 = 2.5hr
second half 160/80 = 2hr
2.5 + 2 = 4.5hr.

Speed = distance/time.
s = 160 + 160/4.5
= 320/4.5 = 71.11.

By using Formula.

2s1s2/s1 + s2.
2 * 80 * 64/80 + 64.
10240/144,
71.11 km/hr.

Avg speed = TD/TT.
Total Distance (TD) = 160 + 160 = 320 km.
Total Time (TT) =160/64 + 160/80 = 9/2 hr.
Avg speed = 320 * 2/9 = 71.11km/hr.

To find the average speed for the first 320 km of the tour, we can use the formula for average speed, which is the total distance traveled divided by the total time taken.

Given:

Distance 1 = 160 km
Speed 1 = 64 km/hr
Distance 2 = 160 km
Speed 2 = 80 km/hr.

We can calculate the total time taken for the first 320 km as follows: Time taken for the first 160 km = Distance 1/Speed 1 Time taken for the next 160 km = Distance 2/Speed 2.

Total time taken = Time taken for the first 160 km + Time taken for the next 160 km.

Total time taken = (Distance 1/Speed 1) + (Distance 2/ Speed 2)
Total time taken = (160/64) + (160/80).

Now, we can find the average speed: Average speed = Total distance / Total time taken Average speed = (Distance 1 + Distance 2)/Total time taken Average speed = 320/ ((160/64) + (160/80)).

By evaluating the expression, we can find the average speed for the first 320 km of the tour.

Total distançe = 160+160=320
Total time = 160/64+160/80 = 4.5 = 9/2.
Av speed = TD/TT.
= 320/9/2.
= 71.11km/h.

We can use,
Avg= 64 + 80/2.
= 144/2.
= 72 kmph.
= 72

So, here the answer is 71.11 kmph.

Can we use Average = (80+64)/2?

Anyone, Please tell me.

Formula use to average speed is 2xy/x+y.
First speed is x = 64,
Second speed is y = 80.
Put the speeds values in the formula.
= 2xy/x+y.
= 2x64x80/64+80,
= 10240/144,
= 71.1111 km/hr ans.

We can apply 2xy/x+y.

Am I right?