Mr. Thomas invested an amount of 13,900 divided in two different schemes A and B at the simple interest rate of 14% p.a. and 11% p.a. respectively. If the total amount of simple interest earned in 2 years be 3508, what was the amount invested in Scheme B?  Pick one:
A) 6200
B) 6300
C) 6400
D) 6500
E) 6600
Let the sum invested in Scheme A be x and that in Scheme B be (13900 - x).   Then, (x x 14 x 2)/100 + ((13900 - x) x 11 x 2)/100 = 3508   28x - 22x = 350800 - (13900 x 22)   6x = 45000   x = 7500.   So, sum invested in Scheme B = (13900 - 7500)= 
<gadget id="calculator">(13900 - 7500)</gadget>
<output>6_400</output>
6400.   answer : 6400
<result>C</result>
Mr. Thomas invested an amount of 13,900 divided in two different schemes A and B at the simple interest rate of 14% p.a. and 11% p.a. respectively. If the total amount of simple interest earned in 2 years be 3508, what was the amount invested in Scheme B?