Aptitude - Time and Distance - Discussion
Discussion Forum : Time and Distance - General Questions (Q.No. 10)
10.
A car travelling with 
of its actual speed covers 42 km in 1 hr 40 min 48 sec. Find the actual speed of the car.
of its actual speed covers 42 km in 1 hr 40 min 48 sec. Find the actual speed of the car.
Answer: Option
Explanation:
| Time taken = 1 hr 40 min 48 sec = 1 hr 40 | 4 | min = 1 | 51 | hrs = | 126 | hrs. |
| 5 | 75 | 75 |
Let the actual speed be x km/hr.
| Then, | 5 | x x | 126 | = 42 |
| 7 | 75 |
 x = |
 |
42 x 7 x 75 |  |
= 35 km/hr. |
| 5 x 126 |
Discussion:
117 comments Page 8 of 12.
Vikram said:
10 years ago
Hai @Ruchir.
Given time is: 1 hr 40 min 48 sec.
Conver hr to sec.
First convert hr to min : 1 hr = 60 min.
Next convert min to sec : 60 min = 3600 sec (1 min = 60 sec).
Finally 1 hr = 3600 sec.
Convert min to sec.
40 min = 40*60 sec = 2400 sec.
Then add 3600+2400+48 = 6048 sec.
1 hr 40 min 48 sec = 6048 sec.
Given time is: 1 hr 40 min 48 sec.
Conver hr to sec.
First convert hr to min : 1 hr = 60 min.
Next convert min to sec : 60 min = 3600 sec (1 min = 60 sec).
Finally 1 hr = 3600 sec.
Convert min to sec.
40 min = 40*60 sec = 2400 sec.
Then add 3600+2400+48 = 6048 sec.
1 hr 40 min 48 sec = 6048 sec.
Ruchir said:
10 years ago
I am not able to understand the conversion please explain me.
Rani said:
10 years ago
How we got 42 as distance?
Komal said:
10 years ago
If a car travelling with a 25 kmph speed which is equal to its 5/7th actual speed then its original/actual speed is 35 kmph.
i.e 5/7 --> 25 i.e
x.1 = 25*7/5.
=> x = 35 kmph.
i.e 5/7 --> 25 i.e
x.1 = 25*7/5.
=> x = 35 kmph.
Dheepak ts said:
1 decade ago
Easy method to convert timings:
First convert everything into seconds.
1 hour 40 mins 48 secs.
= 60*60+40*60+48 secs = 3600+2400+48 secs
= 6048 secs.
Now convert secs to hour by dividing it by 60*60 i.e. 3600.
6048/3600 = 42/25 hours you will get.
Apply it in D = S*T.
First convert everything into seconds.
1 hour 40 mins 48 secs.
= 60*60+40*60+48 secs = 3600+2400+48 secs
= 6048 secs.
Now convert secs to hour by dividing it by 60*60 i.e. 3600.
6048/3600 = 42/25 hours you will get.
Apply it in D = S*T.
Tarun said:
1 decade ago
If a car travelling with 5/7 of its actual speed. Then 35 kmph is possible?
Tarun said:
1 decade ago
Time taken = 1 hr 40 min 48 sec = 1 hr 40 4/5 min.
= 126/75 hrs.
Actual speed X kmph.
Then Xx126/75 = 42.X = 25 kmph.
35 is incorrect.
= 126/75 hrs.
Actual speed X kmph.
Then Xx126/75 = 42.X = 25 kmph.
35 is incorrect.
Mahendra said:
1 decade ago
I want another model for this problem.
Sai said:
1 decade ago
Why should we multiply with 5/7?
Praful said:
1 decade ago
Suppose actual speed is x km/hr.
1 hr 40 min 48 sec = 6048/3600 hr.
42/5/7x = 6048/3600.
x = 35.
1 hr 40 min 48 sec = 6048/3600 hr.
42/5/7x = 6048/3600.
x = 35.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers