time and distance short tricks, tricks for solving time and distance problems
ssc preparation, important competetion questions, current affairs of india, latest question asked in competetion papers,
Hello Aspirants,
Here we are providing you some tricks which can be helpful to solve Time Speed & Distance Questions in Quant Section.
Here we are providing you some tricks which can be helpful to solve Time Speed & Distance Questions in Quant Section.
Type 1:
When you are given two different speeds (s1 and s2) for travelling through a certain distance, and total time (t) for these two journeys:
Formula:
Distance = (S1*S2)/[(S1+S2)t]
When you are given two different speeds (s1 and s2) for travelling through a certain distance, and total time (t) for these two journeys:
Formula:
Distance = (S1*S2)/[(S1+S2)t]
Ex 1: A boy/train goes from A to B at 3 km/hr, back from B to A at 2 km/hr. Total time for these two journeys is 5 hours, then distance from A to B is given by:
Sol:
Distance = Product of speeds/Addition of speeds * Time
D = 3*2/(3+2) * 5 = 6 km
D = 6km
Sol:
Distance = Product of speeds/Addition of speeds * Time
D = 3*2/(3+2) * 5 = 6 km
D = 6km
Ex 2: A boy/train travels from A to B. He covers half distance at 3 km/hr, and other half at 2 km/hr. Total time taken is 5 hours, then distance from A to B is given by:
Sol:
So this time total distance from A to B = (2* Product of speeds)/(Addition of speeds * Time)
D = 2 * [3*2/(3+2) * 5 ]= 12 km
D = 12km
Sol:
So this time total distance from A to B = (2* Product of speeds)/(Addition of speeds * Time)
D = 2 * [3*2/(3+2) * 5 ]= 12 km
D = 12km
Ex 3: A boy/train travels from A to B. He covers 2/3rd distance at 2 km/hr, and rest at 3 km/hr. Total time taken is 24 hours, then distance from A to B is given by:
Sol:
S1 = 2 km/hr, S2 = 3 km/hr, Total time, T = 24 hrs
Distance left = 1 – 2/3 = 1/3
Reciprocate both distances, i.e. D1 = 3/2 and other D2 = 3/1
Distance from A to B = D1*S1 * D2*S2/ (D1*S1 + D2*S2) * T
i.e. 3/2*2 * 3/1*3/ (3/2*2 + 3/1*2) * 24 = 54 km
D = 54km
Sol:
S1 = 2 km/hr, S2 = 3 km/hr, Total time, T = 24 hrs
Distance left = 1 – 2/3 = 1/3
Reciprocate both distances, i.e. D1 = 3/2 and other D2 = 3/1
Distance from A to B = D1*S1 * D2*S2/ (D1*S1 + D2*S2) * T
i.e. 3/2*2 * 3/1*3/ (3/2*2 + 3/1*2) * 24 = 54 km
D = 54km
Type 2:
When you are given two different speeds (s1 and s2) for travelling through a certain distance, and total difference in time (t) is given for these two journeys:
Formula:
Distance = (S1*S2)/[(S1-S2)t]
When you are given two different speeds (s1 and s2) for travelling through a certain distance, and total difference in time (t) is given for these two journeys:
Formula:
Distance = (S1*S2)/[(S1-S2)t]
Ex 1: A boy/train goes from A to B. If speed is 30 km/hr, he/it is late by 10 minutes. If speed is 40 km/hr, he/it reaches 5 minutes earlier, then distance from A to B is given by:
Sol:
Difference in time = 10 – (-5) = 15 minutes or 1/4 hr……..earlier(-5)
Distance = Product of speeds/Difference of speeds * Difference in time
= 30*40/(40-30) * 1/4 = 30 km
D = 30km
Sol:
Difference in time = 10 – (-5) = 15 minutes or 1/4 hr……..earlier(-5)
Distance = Product of speeds/Difference of speeds * Difference in time
= 30*40/(40-30) * 1/4 = 30 km
D = 30km
Ex 2: A train leaves Delhi at 9 AM at 25 km/hr, another train at 35 km/hr leaves Delhi at 2 PM in same direction. How many kilometres from Delhi they will be together?
Sol:
Difference in times = 2 PM – 9 AM = 5 hrs
Distance from Delhi = 25*35/(35-25) * 5
D = 17.5km
Sol:
Difference in times = 2 PM – 9 AM = 5 hrs
Distance from Delhi = 25*35/(35-25) * 5
D = 17.5km
Type 3:
When different speed and time are given to find the original time.Formula:
Original time = (Reciprocal of given speed*t) – t(late)
Original time = (Reciprocal of given speed*t) + t(early)
When different speed and time are given to find the original time.Formula:
Original time = (Reciprocal of given speed*t) – t(late)
Original time = (Reciprocal of given speed*t) + t(early)
Ex 1: Walking at 3/4th of usual speed, person is late by 10 minutes. Find the usual time.
Sol:
Let t be usual time.
Reciprocate speed for time, i.e. 4/3 * t
Person is late by 10 minutes, so (4/3 * t) – t = 10
t = 30 min
Sol:
Let t be usual time.
Reciprocate speed for time, i.e. 4/3 * t
Person is late by 10 minutes, so (4/3 * t) – t = 10
t = 30 min
Type 4:To find the time of halts when the speed with stoppages (s1)and speed without stoppages (s2) is given.
Formula:
Halt time = (s2-s1)/s2
Formula:
Halt time = (s2-s1)/s2
Ex 1: A man/train leaves from A to B. Speed with stoppages = 60 km/hr, speed without stoppages = 80 km/hr. Find the time man/train stop?
Sol:
Minutes per hour the man/ train stops = (80-60)/80 = 1/4 hr = 15 min
Time = 15 min
Sol:
Minutes per hour the man/ train stops = (80-60)/80 = 1/4 hr = 15 min
Time = 15 min
Type 5 :
A & B start at same time towards each other. After meeting each other, they reach their destinations after ‘a’ and ‘b’ hrs respectively.
Formula:
A’s Speed : B’s Speed = √b : √a
A & B start at same time towards each other. After meeting each other, they reach their destinations after ‘a’ and ‘b’ hrs respectively.
Formula:
A’s Speed : B’s Speed = √b : √a
Ex 1: Two, trains, one from Delhi to Mumbai and the other from Mumbai to Delhi, start simultaneously. After they meet, the trains reach their destinations after 4 hours and 9 hours respectively. The ratio of their speeds is:
Sol:
A:B = √b : √a = 3 : 2
A:B = 3:2
Sol:
A:B = √b : √a = 3 : 2
A:B = 3:2
Type 6 :
A man takes ‘a’ hrs to walk to a certain distance and ride back.
A man takes ‘a’ hrs to walk to a certain distance and ride back.
- If riding both ways takes him b hrs, then Walking both ways takes him
[a + (a-b)] hrs - If walking both ways takes him b hrs, then Riding both ways takes him
[a – (b-a)] hrs
Ex 1: A man takes 6 hrs to walk to a certain distance and ride back. If riding both ways takes him 4 hrs, then Walking both ways takes him how much time?
Sol:
T = [a + (a-b)] hrs
T = 6 +2
T = 8hrs
Sol:
T = [a + (a-b)] hrs
T = 6 +2
T = 8hrs
Ex 2: A man takes 5 hrs to walk to a certain distance and ride back. If walking both ways takes him 7 hrs, then Riding both ways takes him how much time?
Sol:
T = [a – (b-a)] hrs
T = 5 – 2
T = 3hrs
Sol:
T = [a – (b-a)] hrs
T = 5 – 2
T = 3hrs
Type 7 :
A man/train leaves from A at x1 AM and reaches Q at y1 AM. Another man/train leaves from Q at x2 AM and reaches P at y2 PM. When they will meet?
Formula:
They will meet at = (x1+y2)/2
A man/train leaves from A at x1 AM and reaches Q at y1 AM. Another man/train leaves from Q at x2 AM and reaches P at y2 PM. When they will meet?
Formula:
They will meet at = (x1+y2)/2
Ex 1: A man/train leaves from P at 6 AM and reaches Q at 10 AM. Another man/train leaves from Q at 8 AM and reaches P at 12 PM. When they will meet
Sol:
Since both takes 4 hrs to reach their destination, so they will exactly at the middle of 6 AM and 12 PM, i.e. at 9 AM.
Sol:
Since both takes 4 hrs to reach their destination, so they will exactly at the middle of 6 AM and 12 PM, i.e. at 9 AM.
Comments
Post a Comment