Aptitude - Problems on Numbers - Discussion
Discussion Forum : Problems on Numbers - General Questions (Q.No. 13)
13.
A number consists of 3 digits whose sum is 10. The middle digit is equal to the sum of the other two and the number will be increased by 99 if its digits are reversed. The number is:
Answer: Option
Explanation:
Let the middle digit be x.
Then, 2x = 10 or x = 5. So, the number is either 253 or 352.
Since the number increases on reversing the digits, so the hundred's digits is smaller than the unit's digit.
Hence, required number = 253.
Discussion:
22 comments Page 3 of 3.
Jadala Pramoul said:
3 years ago
@Laxmikanta.
Thank you so much you explained in a very simple and easy manner.
Thank you so much you explained in a very simple and easy manner.
Jetha lal tapuu ke papa said:
3 years ago
I have assumed that X ,Y, Z are the three numbers and their positions are 100X+10Y+Z
now;
According to the que;
X+Y+Z=10---> (1)
and
X+Z=Y -------> (2).
From eq 1 and eq 2.
We get;
Y=5 ----> (3)
from eq2 and eq 3.
we get;
X+Y=5----->(4)
now from here, it is sure that number would have 5 digit in its middle.
a/c to que
(100X+ 10Y+Z) +99= 100Z+10Y+X
99= 99Z-99X
1= Z-X------------> (5)
from eq 4 and eq 5;
we get X=2.
Z=3.
So the number is 253 the answer.
now;
According to the que;
X+Y+Z=10---> (1)
and
X+Z=Y -------> (2).
From eq 1 and eq 2.
We get;
Y=5 ----> (3)
from eq2 and eq 3.
we get;
X+Y=5----->(4)
now from here, it is sure that number would have 5 digit in its middle.
a/c to que
(100X+ 10Y+Z) +99= 100Z+10Y+X
99= 99Z-99X
1= Z-X------------> (5)
from eq 4 and eq 5;
we get X=2.
Z=3.
So the number is 253 the answer.
(13)
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