A part of certain sum of money is invested at 10% per annum and the rest at 12% per annum, if the interest earned in each case for the same period is equal, then ratio of the sums invested is?
Choose the correct choice from the following answers.
A) 4 : 2
B) 4 : 8
C) 4 : 3
D) 4 : 0
E) 6 : 5

Rationale: "12 : 10 = 6 : 5 answer : e"
Answer: E