A positive two-digit integer ab, where a is the tens digit and b is th

Question

A positive two-digit integer ab, where a is the tens digit and b is the units digit, when divided by the product of its digits equals to 3. If you add 18 to the two digit integer the result will be a two-digit integer ba, where b is the tens digit and a is the units digit. What is the value of the original two-digit integer?

A. 15
B. 24
C. 36
D. 42
E. 51

A. 15
B. 24
C. 36
D. 42
E. 51

IanStewart · Answer

If we add 18 to the right answer, with digits AB, we need to get a number with those digits reversed, BA. Only 24 works.

There isn't any reason to consider the first half of the question stem with these answer choices.

Babineaux · Answer

Just going through the ans choices,

Original number when divided by their product result in 3.

Only 15 and 24 works.

Again, when 18 is added it changes it's orientation.

Only 24 works and results in 42.

IMO ans is B.

kris19 · Answer

isn't it a straight forward substitution ?
ab + 18 ==> ba
24 + 18 ==>42

Answer B

saurabh851 · Answer

ANS:B
Original No: ab =>10a+b
(10a+b)/a x b = 3----------(1)
Given: 
ab+18 = ba
10a+b+18 = 10b+a
Upon solving, b=2+a-------(2)

Put (2) in equation (1)
will get, a=2
then , b=4

Number is 24...

Hope it helps..

Lipun · Answer

Best method for such questions is to directly check the values in answer options.
Upon checking we find that 24 satisfies the given conditions.

So, ans = 24

bM22 · Answer

Given:
Eq 1: (10a+b)/ab = 3.
Eq 2: 10a + b +18 = 10b + a
=> 9a - 9b = 18.
=> a - b = 2.
Looking at the options only 2 satisfy the criteria, so A,C E are out.

Then we substitute B in eq. 1, we get
10*2 + 4 = 3 * 2* 4 
24 = 24.

Answer B.

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A positive two-digit integer ab, where a is the tens digit and b is th

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A positive two-digit integer ab, where a is the tens digit and b is th

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