Math's formulation of different ways!!

wizkid

New member
A person is travelling in a car at a constant speed. at an instance the mile stone shows the distance of 2 digits.after 1 hr another milestone reads the
revesed number.after another hr a milestone reads the same two digits seperated by a zero. what is the distance to be travelled.


Here is a equation based approach to solve this question.

Let the value shown in the first mile stone be XY, where X and Y take values between 1 and 9 as the tens place of a 2-digit number cannot be '0'.

Therefore, the value shown in the second milestone is YX.

The value shown in the third milestone is XOY.

The value of the first milestone is therefore, 10X + Y
Second milestone value is 10Y + X and
The value of the third milestone is 100X + Y

We know that the distance traveled between the first and second milestone is the same as the distance traveled between the second and third milestone.

Therefore, 10Y + X - (10X + Y) = 100X + Y - (10Y + X)
Solving this equation, we get 9Y - 9X = 99X - 9Y
or 18Y = 108X or Y = 6X.

Now, if X takes any value other than '1', Y will become a 2-digit number.

Therefore, the first milestone is 16, the second one is 61 and the third one 106.

The distance traveled each hour = 61 -16 = 45.

Hence, speed = 45 mph
 
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