The ratio of two natural numbers is 5:6. If a certain number is added to both the numbers, the ratio becomes 7:8. If the larger number exceeds the smaller number by 10, find the number added? Choose the correct choice from the following answers.
A) 27
B) 298
C) 20
D) 28
E) 12
Let the two numbers be 5x and 6x.   Let the number added to both so that their ratio becomes 7:8 be k.   (5x + k)/(6x + k) = 7/8   42x = 7k =&gt; k = 2x.   6x - 5x = 10 =&gt; x = 10   k = 2x = 20.   Answer: 20
<result>C</result>
The ratio of two natural numbers is 5:6. If a certain number is added to both the numbers, the ratio becomes 7:8. If the larger number exceeds the smaller number by 10, find the number added?