Aptitude - Time and Distance - Discussion

Discussion Forum : Time and Distance - General Questions (Q.No. 9)
9.
A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is:
35.55 km/hr
36 km/hr
71.11 km/hr
71 km/hr
Answer: Option
Explanation:

Total time taken = 160 + 160 hrs. = 9 hrs.
64 80 2

Average speed = 320 x 2 km/hr = 71.11 km/hr.
9

Discussion:
65 comments Page 1 of 7.

Thabisha said:   3 weeks ago
Here we can use the formula.

Equal distance and different speed [2xy/x+y].

Chidara Susmitha said:   2 months ago
(2s1s2)/s1 + s2 = average speed.
(2.64.80)/64 + 80 = 71.11.
(2)

BALAKRISHNAN R said:   1 year ago
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.
(14)

Balamurugan said:   1 year ago
@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.
(18)

Bloci said:   2 years ago
By using Formula.

2s1s2/s1 + s2.
2 * 80 * 64/80 + 64.
10240/144,
71.11 km/hr.
(11)

Aby said:   2 years ago
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.
(7)

Shanmuk Siva Naarappa R said:   2 years ago
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.
(2)

Haseeb said:   3 years ago
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.
(23)

Kunal Savle said:   4 years ago
We can use,
Avg= 64 + 80/2.
= 144/2.
= 72 kmph.
= 72

So, here the answer is 71.11 kmph.
(49)

Suyog said:   4 years ago
Can we use Average = (80+64)/2?

Anyone, Please tell me.
(18)


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