Question

Rhianna invests $1200 in stock and bonds. The stock pays 9% interest and the bonds pay 6% interest. If the total ANNUAL interest is $96, how much is invested in the stock alone?

Answer 1

0.06x+0.09 (1200-x)=96
Solve for x
X=400 at 6%

1200-400=800 at 9%

Answer 2

$800

Explanation:

Based on the question, annual interest rate ($96) is equal to

bond price*0.06 + stock price*0.09

where bond price = 1200 - stock price

hence,

(1200 - stock price)*0.06 + stock price*0.09 = 96

1200*0.06 - stock price*0.06 + stock price*0.09 = 96

72 - stock price*0.06 + stock price*0.09 = 96

stock price*0.09 - stock price*0.06 = 96 - 72

stock price(0.09 - 0.06) = 24

stock price = 24/0.03

stock price = 800