When a two digit number is multiplied by the sum of its digits, the product is 424.When the number obtained by interchanging its digits is multiplied by the sum of the digits, the result is 280. The sum of the digits of the given number is ?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 ie 8.
(10a + b)(a + b) = 424
(10b + a)(a + b) = 280
(10a + b) / (10b + a) = 424/280
= 53/35
ab/ba = 53/35
ab = 53
ba = 35
hence, sum of digits = 8