Aptitude - Time and Distance - Discussion
Discussion Forum : Time and Distance - General Questions (Q.No. 11)
11.
In covering a distance of 30 km, Abhay takes 2 hours more than Sameer. If Abhay doubles his speed, then he would take 1 hour less than Sameer. Abhay's speed is:
Answer: Option
Explanation:
Let Abhay's speed be x km/hr.
| Then, | 30 | - | 30 | = 3 |
| x | 2x |
6x = 30
x = 5 km/hr.
Discussion:
209 comments Page 5 of 21.
Abdul quddus said:
6 years ago
S1= s = d/t = d/t+2.
S2 = 2s = d/t-1.
S/2s = 1/t+2/1/t-1.
1/2 = t-1/t+2.
t+2 = 2t-2.
t = 4.
S = D/T = 30/6 = 5.
S2 = 2s = d/t-1.
S/2s = 1/t+2/1/t-1.
1/2 = t-1/t+2.
t+2 = 2t-2.
t = 4.
S = D/T = 30/6 = 5.
Divijay said:
6 years ago
Superb and useful explanation, thanks @Devi.
Shivangi said:
6 years ago
Thanks @Devi.
Murali said:
6 years ago
Thanks @Shanti.
Shonti said:
6 years ago
(30/Sa-30/Ss) = 2.
(30/2Sa-30/Ss) = -1.
30/Sa - 2 = 30/2Sa +1.
Sa = 5.
(30/2Sa-30/Ss) = -1.
30/Sa - 2 = 30/2Sa +1.
Sa = 5.
Prakash said:
6 years ago
In simple words:
The time taken to cover the distance of 30 km is always the same in both conditions.
let the speed of Abhay be x.
Now the time taken for 1st condition =time taken for 2nd condition.
Therefore,(30/x)+2 = (30/2x)-1.
(30/x)-(30/2x) = 3.
x = 5.
The time taken to cover the distance of 30 km is always the same in both conditions.
let the speed of Abhay be x.
Now the time taken for 1st condition =time taken for 2nd condition.
Therefore,(30/x)+2 = (30/2x)-1.
(30/x)-(30/2x) = 3.
x = 5.
Anudeep said:
6 years ago
Distance=30,
Time of sameer=s,
Time taken by abhay = 2hrs+s.
The Speed of Abhay= 30/(2hrs+s),
Time is taken by Abhay after doubling speed = s-1hr.
Speed of abhay= 60/(s-1hr),
We know that both are the speeds of Abhay, So both the speeds are equal.
30/(2hrs+s) = 60/(s-1hr),
30(s-1hr) = 60(2hr+s).
150hr = 30s,
s=5.
So, the final answer is 5.
Time of sameer=s,
Time taken by abhay = 2hrs+s.
The Speed of Abhay= 30/(2hrs+s),
Time is taken by Abhay after doubling speed = s-1hr.
Speed of abhay= 60/(s-1hr),
We know that both are the speeds of Abhay, So both the speeds are equal.
30/(2hrs+s) = 60/(s-1hr),
30(s-1hr) = 60(2hr+s).
150hr = 30s,
s=5.
So, the final answer is 5.
SURENDRA SINGH NEGI said:
6 years ago
Case 1:
Abhay's speed = Y.
Sameer has taken time = T,
Then, Y = 30km/T + 2.
Case 2:
Abhay's speed = 2Y.
Abhay's taken time = T-1.
Then, 2Y=30km/T-1.
We put the value of Y in case 2.
Then , 2*30km/T+2 = 30km/T+1.
60T+60=30T+60
30T=120.
T=4.
Put the value of T in case 1.
Y=30km/4hrs + 2hrs.
= 30km/6hrs.
= 5 km/hrs.
Abhay's speed = Y.
Sameer has taken time = T,
Then, Y = 30km/T + 2.
Case 2:
Abhay's speed = 2Y.
Abhay's taken time = T-1.
Then, 2Y=30km/T-1.
We put the value of Y in case 2.
Then , 2*30km/T+2 = 30km/T+1.
60T+60=30T+60
30T=120.
T=4.
Put the value of T in case 1.
Y=30km/4hrs + 2hrs.
= 30km/6hrs.
= 5 km/hrs.
Krutika said:
6 years ago
Thanks for the answer @Devi.
Divagar said:
6 years ago
Thanks for the answer @Devi.
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