John invested some money in 5% stock at 100.If David wants to invest in an equally good 10% stock ,he must purchase a stock worth of : Choose the correct choice from the following answers:
A) Rs. 250	B) Rs. 200	C) Rs. 220	D) Rs. 100	E) Rs. 180
Solution   For an income of Rs. 5, investment = Rs. 100   For an income of Rs. 10, investment = Rs.(100/5x10) = Rs. 200   Answer Rs. 200
<result>B</result>
John invested some money in 5% stock at 100.If David wants to invest in an equally good 10% stock ,he must purchase a stock worth of :