Aptitude - Problems on Numbers - Discussion
Discussion Forum : Problems on Numbers - General Questions (Q.No. 9)
9.
In a two-digit, if it is known that its unit's digit exceeds its ten's digit by 2 and that the product of the given number and the sum of its digits is equal to 144, then the number is:
Answer: Option
Explanation:
Let the ten's digit be x.
Then, unit's digit = x + 2.
Number = 10x + (x + 2) = 11x + 2.
Sum of digits = x + (x + 2) = 2x + 2.
(11x + 2)(2x + 2) = 144
22x2 + 26x - 140 = 0
11x2 + 13x - 70 = 0
(x - 2)(11x + 35) = 0
x = 2.
Hence, required number = 11x + 2 = 24.
Discussion:
42 comments Page 3 of 5.
Anjali said:
9 years ago
Correct answer @Naresh.
BASAVRAJ said:
9 years ago
Well said. Your explanation is good @Naresh.
Venkat said:
1 decade ago
If option A is correct according to naresh why not C, as it is same to a when we add up ?
Mamta said:
1 decade ago
confusing... can it be little more simplified
Bharathi said:
1 decade ago
How unit digit is x+2 ?
Gupta said:
1 decade ago
In the question it is clearly mentioned that units digit is 2 more than tens digit, then by observing the options only in 24 units digit(i.e.4 ) is more than 2 with tens digit(i.e.2).
Kranth said:
1 decade ago
Confusing in the answer. There is not clearence.
Karthi said:
1 decade ago
It is confusing please explain about 10x.
Soumya said:
1 decade ago
Explanation about 10x
eg:123 means 100+20+3
in question its given tat unit's digit exceeds its ten's digit by 2 ,so units place is x+2 n tens place is 10x....
eg:123 means 100+20+3
in question its given tat unit's digit exceeds its ten's digit by 2 ,so units place is x+2 n tens place is 10x....
Sandeep said:
1 decade ago
Nice explanation naresh.
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