Rs 3500 is divided into two parts such that one part is put out at 3% and the other at 5%. If the annual interest earned from both the investments be Rs 144, find the first part.
Choose the correct answer:
A) s 4000
B) s 2800
C) s 1800
D) s 1500
E) s 1550

Rationale: "explanation : average rate = ( 144 / 3500 ) * 100 = 4.11 ratio = 8.85 : 11.14 so , first part = ( 8.85 / 20 ) * 3500 = rs 1550 . answer : e"
Answer: E