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There are three keys concepts:

Ratios

One of in this term there is a relation between the other two terms

Speed

So,

is the top of the numerator as well as also a top of the numerator.

Approach

The third key concept is how to approach the question. The questions are two types of approach:

(1) Constant distance question and (2) Constant time question

A Man Takes 5 Hr 45 Min in Walking to Certain Place and Riding Back. He Would Have Gained 2 Hrs by Riding Both Ways. The Time He Would Take to Walk Both Ways Is?

A person who can walk and how to ride the horse

He takes walking to certain place and riding back time

He would have gained 2 hrs by both riding and walking:

Time taken to walk both ways

I Leave My Home Every Day at 8: 00 Am. One Day, I Left My Home at My Normal Time and Travelled the First Half of the Distance at 2 ⁄ 3 of Original Speed, What Should be My Speed for the Second Half So That I Reach My Office in Time?

A person who leaves home every day at 8: 00 am

One day, some reason he took speed

Speed distance

So, all would be cancel from the top and all would be cancel from the bottom

In 2nd scenario, time take is . It means that is double record.

A Train Goes from Station a to Station B Every Day. One Day, It Travelled 4 ⁄ 5 of Its Original Speed Because of Engine Trouble at a and Reached Station B at 6: 15 Pm. If the Trouble Had Occurred After the Train Had Travelled 100 Km from a, the Train Would Have Reached B at 6: 00. Find Its Original Speed?

Train goes from station A to station B

Original speed

It is remember that the distance is remaining constant

New speed

Difference between times in this scenario is important.

In simple way:

Time and the speed in 1st scenario it reduced

Time would increase by a factor of

Difference

A covered a distance of 96 km two hours faster than he had planned to. This he achieved by travelling 1 km more every hour than he intended to cover every 1 hour 15 minutes. What was the speed at which A traveled during the journey?

96 km covered in two different ways.

Normal distance

2nd scenario

Of course is not possible.

Real speed

So, speed is 12 km A traveled during the journey.

Bob Picks His Son Every Day from School. School Timings Are Till 5 Pm Daily, but Today It Was Till 4 Pm. His Son, Walks Towards the House. Bob, Unaware of this Fact, Leaves His House as Usual, Meets His Son on Way, Scolds Him for Leaving Alone and Brings Him to House. Bob Realizes That He Had Saved 40 Minutes That Day. What is the Ratio of the Speed of Bob to His Son?

Bob is father and a child who is studying in the school.

In normal day Bob is picked his to school at 5: 00 pm.

On one day, he was till 4: 00 pm and child was started walking from home.

Son would walk to 40 minutes

So, ratio of speed

Ravi Who Lives in Countryside Caught a Train for Home Earlier Than Usual Yesterday. His Wife Normally Drives to Station to Meet Him. But Yesterday He Set Out on Foot from the Station to Meet His Wife on the Way. He Reached Home 12 Minutes Earlier at 6′O Clock. The Car Travels at 5 Times Ravi՚s Speed. At What Time Would He Have Reached Home if His Wife Had Met Him at the Station?

A guy who lives in countryside

His wife every day she would drive from home to the station

But one day, he set out on foot from the station to meet his wife on the way so, his wife meet in the midway.

So, a guy reached home at 12 min earlier at 6 o′clock hence, 6 min to walk forward and 6 min to back

The car travels at 5 times Ravi՚s speed:

How much time he would goes home

Hence, he would reach 24 min earlier at 6 o′clock

So, he would reach at 5: 36

Two Trains Start Together from Opposite Stations. After They Cross One of Them Takes 9 Hours to Reach the Destination and Other 25 Hours. Find the Ratio of Their Speeds?

There are two trains start together from opposite stations.

After crossing, they take 9 hours and 25 hours respectively to reach the opposite stations.

Let՚s try to solve this problem,

There are two trains A and B, ration of the speed

We know that, the meeting place happens it՚s a constant of time scenario

Let՚s try to understand, what would be the ratio of times they would take to reach the opposite end after covering first distances.

Ratio of time to reach the opposite end

after meeting to reach the opposite end

Ratio of the time taken after meeting of the inverse the ratio of the speeds

A Man Started from Home at 14: 30 Hours and Drove to a Village, Arriving There when the Village Clock Indicated 15: 15 Hours. After Staying 25 Minutes, He Drove Back by a Different Route of Length (5 ⁄ 4) Times the First Route at a Rate Twice as Fast, Reaching Home at 16: 00 Hours. As Compared to the Clock at Home the Village Clock is ________ Fast ⁄ Slow?

A man started from home at 14: 30 to village

Village clock after 25 minutes, time in clock

They get back home at 16: 00

Let՚s take original time and final time

A rate twice as fast means double speed at going back at home.

Therefore, half of the original time of

So, relation between final time and original time

We cannot know the correct time, so, 15: 15 and 15: 40 is wrong time.

Fast by , we assume that and

Correct substitute of :

So, the clock will be 5 min fast

A Train Approaches a Tunnel AB. Inside the Tunnel is a Cat Located at a Point That is 3 ⁄ 8 of the Distance AB Measured from the Entrance a. When the Train Whistles the Cat Runs. If the Cat Moves to the Entrance of the Tunnel a, the Train Catches the Cat Exactly at the Entrance. If the Cat Moves to the Exit B, the Train Catches the Cat Exactly at the Exit. The Speed of the Train is Greater Than the Speed of the Cat by What Order?

There are four scenarios are given in this question.

Train approach a tunnel AB, the tunnel is a cat located inside.

There are two scenarios: if the cat moves to the entrance of the tunnel A, and if the cat moves to the exit tunnel B.

In 1st case:

2nd case:

Equation:

Solve it:

Ratio of the speed

Next: Relative Speed

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