If the annual rate of simple interest increases from 10% to 12 1/2 %, a man's yearly income increases by Rs. 1250. His principal in Rs. is?
Choose the correct option
A) 50009 B) 50000 C) 50011 D) 50077 E) 50027
Let the sum be Rs. x. Then,   (x * 25/2 * 1/100) - (x * 10 * 1)/100 = 1250   25x - 20x = 250000   x = 50000   Answer: 50000
<result>B</result>
If the annual rate of simple interest increases from 10% to 12 1/2 %, a man's yearly income increases by Rs. 1250. His principal in Rs. is?