Aptitude - Problems on Numbers - Discussion
Discussion Forum : Problems on Numbers - General Questions (Q.No. 5)
5.
A two-digit number is such that the product of the digits is 8. When 18 is added to the number, then the digits are reversed. The number is:
Answer: Option
Explanation:
| Let the ten's and unit digit be x and | 8 | respectively. |
| x |
| Then, |  |
10x + | 8 |  |
+ 18 = 10 x | 8 | + x |
| x | x |
10x2 + 8 + 18x = 80 + x2
9x2 + 18x - 72 = 0
x2 + 2x - 8 = 0
(x + 4)(x - 2) = 0
x = 2.
Discussion:
43 comments Page 4 of 5.
Sunny said:
1 decade ago
Why didn't you take 8x, 1/x and solve the problem?
Banty kumar.biet davangere said:
1 decade ago
xy=8,xy+18=yx;
put xy=8 than
8+18=24
so,
xy=24 ans
put xy=8 than
8+18=24
so,
xy=24 ans
May said:
1 decade ago
Oh. You great and feeling in so easy. Thanks you.
Mahesh said:
9 years ago
Could anyone please provide the shortcut method?
Naina said:
8 years ago
Hi @Gopinath.
How 8+18 = 24?
I think its 26.
How 8+18 = 24?
I think its 26.
Ayesha said:
10 years ago
9x2+18x-72.
How it is simplified further?
How it is simplified further?
Manav Pawar said:
3 years ago
Anyone, please explain this to get it.
(5)
Sam said:
9 years ago
Can anyone explain it in another way?
(1)
Bgnr said:
9 years ago
What is unit, ten digit and product.
Jason said:
6 years ago
I am not understanding this answer.
(2)
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