Distance between Lucknow and Patna is 300 km. Mayank leaves at a speed...
One of the ways of solving this question is going through equations. But after a certain stages we will be required to start assuming the values because all the data are not given.
Another way of doing this problem is: Start working by assuming some values. Let us assume the speed of Mayank =10 km/h. In three hours he has covered 30 km. Now Sharat starts with a speed of 20 km/h. He will take 3 hours to meet Mayank. Till that time, the total distance covered by Mayank = 60 km.
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Distance between Lucknow and Patna is 300 km. Mayank leaves at a speed...
Let us assume mayank is travelling with 10km/hr ; distance covered by him in 3hrs is 30kms.
speed of sharat is 20 km/hr .
lcm of their speed is i.e 10 and 20 >30 is 60
hence they will meet after 6hrs mayank has started hence distance covered by mayank in 6hrs is 60km
Distance between Lucknow and Patna is 300 km. Mayank leaves at a speed...
Given: Distance between Lucknow and Patna = 300 km
Mayank's speed = x km/h
Sharat's speed = (x+10) km/h
Let's assume that both Mayank and Sharat meet at a distance of d km from Lucknow.
After three hours, Mayank would have covered a distance of 3x km (as he travels for 3 hours).
Let's say Sharat takes t hours to meet Mayank after he starts his journey.
Distance covered by Sharat in t hours = t(x+10)
Distance covered by Mayank in t hours = t(x)
Total distance covered by both of them to meet = d
Therefore, we can form an equation based on the above information:
3x + t(x+10) = d ----(1)
Also, we know that the total distance between Lucknow and Patna is 300 km. Therefore, the total time taken by both Mayank and Sharat to meet each other should be:
t + 3 = (300/d) ----(2)
We need to find the distance covered by Mayank before they meet, which is 3x.
To solve this problem, we can use trial and error method by substituting different values of x until we find the one that satisfies both equations (1) and (2).
Let's start with x = 20 km/h
From equation (2), we get:
t + 3 = (300/d)
t = (300/d) - 3
Substituting x = 20 in equation (1), we get:
3(20) + t(30) = d
60 + 30t = d
Substituting the value of t from equation (2) in the above equation, we get:
60 + 30[(300/d) - 3] = d
Simplifying the above equation, we get:
d^2 - 240d - 5400 = 0
Using the quadratic formula, we get:
d = 174 or d = -30
Since distance cannot be negative, we can consider d = 174 km.
Substituting d = 174 km in equation (1), we get:
3x + t(x+10) = 174
3(20) + t(30) = 174
t = 3
Therefore, Mayank covers a distance of 3x = 60 km before they meet.
Hence, the correct answer is option (B).