Mr. Karthik drives to work at an average speed of 48 km/hr. Time taken to cover the first 60% of the distance is 20 minutes more than the time taken to cover the remaining distance. Then how far is his office ?
Answers
Answer:
His office is 80 km far
Step-by-step explanation:
Let total distance be ' x ' km
Since we know,
Time = Distance / Speed
Let,
Time taken to cover remaining ( 100 - 60 ) = 40% of distance ' x ' = t1
t1 = (40% of x) / 48
t1 = ( 40 * x ) / 100 * 48
Let t2 be the time to cover first 60% of the distance ' x ' , that is,
t2 = ( 60 % of x ) / 48
t2 = ( 60 * x ) / ( 100 * 48 )
According to question,
Time taken to cover the first 60% of the distance is 20 minutes more than the time taken to cover the remaining distance, that is,
t2 = t1 + 20 min
We know,
1 min = 1/60 hr
20 min = 1 / 60 * 20 = 20 / 60 hr
t2 = t1 + 20/60
Substituting value of t1 and t2
( 60 * x ) / ( 100 * 48 ) = ( 40 * x ) / ( 100 * 48 ) + 20 / 60
x / 80 = x / 120 + 20/60
x / 80 = ( x + 40 ) / 120
x / 2 = ( x + 40 ) / 3
3x = 2x + 80
3x - 2x = 80
x = 80
Hence,
His office is 80 km far