Aptitude - Problems on Numbers - Discussion
Discussion Forum : Problems on Numbers - General Questions (Q.No. 4)
4.
The difference between a two-digit number and the number obtained by interchanging the digits is 36. What is the difference between the sum and the difference of the digits of the number if the ratio between the digits of the number is 1 : 2 ?
Answer: Option
Explanation:
Since the number is greater than the number obtained on reversing the digits, so the ten's digit is greater than the unit's digit.
Let ten's and unit's digits be 2x and x respectively.
Then, (10 x 2x + x) - (10x + 2x) = 36
9x = 36
x = 4.
Required difference = (2x + x) - (2x - x) = 2x = 8.
Discussion:
45 comments Page 3 of 5.
Pavithra said:
1 decade ago
I get the answer as 16.
Diff in digits: (x+y)-(x-y)
=2y
=2(2x)
=4x.
Finding the value of x we get, x=4;
So ans = 4(4) = 16.
Diff in digits: (x+y)-(x-y)
=2y
=2(2x)
=4x.
Finding the value of x we get, x=4;
So ans = 4(4) = 16.
Deepak said:
1 decade ago
In the first condition, we get,
10x+y-(10y-x) = 36.
So, 9x-9y = 36.
By solving this we get x-y = 4. Thats all.
10x+y-(10y-x) = 36.
So, 9x-9y = 36.
By solving this we get x-y = 4. Thats all.
Rishitha said:
9 years ago
Can anyone explain what happens after 12k = 48 and 21k = 84?
After we do this how do we get the final answer?
After we do this how do we get the final answer?
Harshit said:
6 years ago
Correct answer should be 16. Ten's digit is X and Unit digit is 2X as the ratio given is 1:2 and not 2:1.
Virendra said:
1 decade ago
In question diff is given i.e. 36 and ratio is 1:2
We just find out such a pair without calculating.
We just find out such a pair without calculating.
Priya said:
1 decade ago
Can anyone explain why do we take (y+x)-(y-x) in the last step rather than 10x+y-(10y-x) ?
Ramya said:
2 decades ago
Hi I could not understand this problem. Can anyone explain this more clearly please?
(1)
Karthik said:
5 years ago
X is in units position and why is in ten's position. So the answer should be 16.
Santosh said:
1 decade ago
Why we have to take 2x in units place rather than x ? can any one explain.
Sikha said:
1 decade ago
It can't b (x+y) - (x-y).
Rather it could be (10x +y) - (10y + x).
Rather it could be (10x +y) - (10y + x).
(1)
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