Aptitude - Problems on Numbers - Discussion
Discussion Forum : Problems on Numbers - General Questions (Q.No. 6)
6.
The sum of the digits of a two-digit number is 15 and the difference between the digits is 3. What is the two-digit number?
Answer: Option
Explanation:
Let the ten's digit be x and unit's digit be y.
Then, x + y = 15 and x - y = 3 or y - x = 3.
Solving x + y = 15 and x - y = 3, we get: x = 9, y = 6.
Solving x + y = 15 and y - x = 3, we get: x = 6, y = 9.
So, the number is either 96 or 69.
Hence, the number cannot be determined.
Discussion:
40 comments Page 3 of 4.
Dipak said:
9 years ago
Agree @Jagdish.
Farah said:
1 decade ago
I don't understand the technique used guide me.
Sundar said:
1 decade ago
@Dominic
You are wrong. The given answer is correct.
I want to ask a question to you.
Assume your height is 165 cm and your friend's height is 170 cm.
Now tell me what is the height-difference between you and your friend?
Is it 5 cm or -5cm ?
We usually write difference between x and y as
X ~ Y NOT as X - Y.
Hence the given answer 'Cannot be determined' is correct.
You are wrong. The given answer is correct.
I want to ask a question to you.
Assume your height is 165 cm and your friend's height is 170 cm.
Now tell me what is the height-difference between you and your friend?
Is it 5 cm or -5cm ?
We usually write difference between x and y as
X ~ Y NOT as X - Y.
Hence the given answer 'Cannot be determined' is correct.
Ramesh said:
1 decade ago
I agree with Sundar.
Moola V reddy said:
1 decade ago
I agree with Dominic
always read the question carefully
1.sum of the two digits
2.difference between them
sundar said good example of difference
but there is no sum
always read the question carefully
1.sum of the two digits
2.difference between them
sundar said good example of difference
but there is no sum
Sally said:
1 decade ago
Could somebody explain why we are not taking the tens digit as 10x and the ones digit as y, Like it was done in the previous questions?
Mehran said:
1 decade ago
Assumed Number = XY.
X-Y = 15----- (i)
X+Y = 3 ------ (ii)
By solving (i)&(ii) we reach at;
X = 9 & Y = 6.
So, Assumed Number is 96,
Which satisfy both equations (i) & (ii).
If we take 69 that is not appropriate because in Equation (ii).
It comes with negative value of -3.
So, correct and answer is 96 that is determined here.
X-Y = 15----- (i)
X+Y = 3 ------ (ii)
By solving (i)&(ii) we reach at;
X = 9 & Y = 6.
So, Assumed Number is 96,
Which satisfy both equations (i) & (ii).
If we take 69 that is not appropriate because in Equation (ii).
It comes with negative value of -3.
So, correct and answer is 96 that is determined here.
S Vishnu Vardhan said:
1 decade ago
Could somebody explain why we are not taking the tens digit as 10x and the ones digit as y, Like it was done in the previous questions?
Ajay said:
1 decade ago
Please explain why we are not taking the tens digit as 10x and the ones digit as y, Like it was done in the previous questions?
Balu said:
1 decade ago
Please why we not take tens digit as 10x and unit digit as y. Please explain as it taken in previous question.
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