Aptitude - Problems on Numbers - Discussion

As ratio of the numbers is 1:2 and it's 2 digit number so possible numbers are only - 12, 24, 36 and 48.

Among those 48 and 84 (reversed 48) gives difference of 36.

So, the digit is 48.

The sum of digits, 8 + 4 = 12
Difference of digits, 8 - 4 = 4
Required difference. 12 - 4 = 8.

So after devoting 30 min, finally I got this! Hopes this will help you all.

Let's take a two-digit no. = XY( 10x +y)

Imp =suppose 27=2 @tenth +7 @unit)

Ist condition:
Ratio is 1:2
Let's assume x = a.
Y= 2a.

10x+y = 10 *a +2a = 10a + 2a = 12a --->(1)
10y+x = 10 * 2a +a =20a + a = 21a ---> (2).

Difference between.
21a - 12a = 36,
9a = 36,
a = 4.

So,
Fill the value in (1,(2).
I.e. 12a =12*4 = 48
21a = 21*4 = 84.
Sum of digits=4 +8 = 12.
Difference = 8-4 = 4.
Differ. between sum and subtraction,
12-4 = 8.
Hope, I am able to explain you simply as possible.

Let's assume 2 digit number is 10.

10x - 01x = 36,
9x = 36,
x = 4.
Coming to question; 1:2;
1x:2x.
1x4: 2x4.
4:8.
Then the answer is 8.

Ratio is 1:2

we will consider 1 and 2 as the numbers.
And have variable x after the subtracting.
then (21 -12)x=36.

Then 9x=36

And x=4 .

And have 2x for the second number which is 8.
the difference is 8-4 = 4.
the sum of 8+4 = 12.

Therefore the difference is 12-4 = 8.

From 3rd question,we can say x-y=4.

We have to find diff of ( sum of digits n diff of digits).
(X+y)-(x-y)=0.
X+y=4.
From 2 equations,we get X=4, sub X value then y=0,
So 2 numbers are 40 and 04,
Sum is 44,diff is 36.
So, diff is 44 - 36 = 8.

The given number is 36 which is +ve So the original number should be greater
Ex:
If ab is two-digit number b is in unit place and a is in 10th place (.etc..hundreds, tens, units)

Now the given ratio is 1:2 says that the ratio between 10s or 1s
The first number must greater than the reverse digit number.
So we give 2x in 10th place in the first number.
(Number)(10*2x+x)-(Reverse no-Small)(10x+2x)=36.
By solving X=4.

Then they said to find the sum and diff of number.
Ans=(2x+x)-(2x-x).
By solving;
We get the Ans is 8.

Thanks @Chinnadurai.

X is in units position and why is in ten's position. So the answer should be 16.

How come 10 here? Please explain.

I am not understanding it, please someone explain me.