The amount of an investment will double in approximately 70/ p years, where p is the percent interest, compounded annually. If Thelma invests $ 40,000 in a long-term CD that pays 5 percent interest, compounded annually, what will be the approximate total value of the investment when Thelma is ready to retire 42 years later?  Choose the correct choice from the following choices:
A) $ 280,000	B) $ 320,000	C) $ 360,000	D) $ 450,000	E) $ 540,000
The amount of an investment will double in approximately 70/ p years, where p is the percent interest, compounded annually. If Thelma invests $ 40,000 in a long-term CD that pays 5 percent interest, compounded annually, what will be the approximate total value of the investment when Thelma is ready to retire 42 years later?   The investment gets doubled in 70/p years. Therefore, the investment gets doubled in   70/5= 
<gadget id="calculator">  70/5</gadget>
<output>14</output>
every 14 years. After 42 years, the investment will get doubled 42/14= 
<gadget id="calculator">42/14</gadget>
<output>3</output>
3 times.   So the amount invested will get doubled thrice.   So, 40000 *2= 80000   80000*2= 
<gadget id="calculator">80000*2</gadget>
<output>160_000</output>
160000   160000*2= 
<gadget id="calculator">160000*2</gadget>
<output>320_000</output>
320000   Hence, the answer is $ 320,000.
<result>B</result>
The amount of an investment will double in approximately 70/ p years, where p is the percent interest, compounded annually. If Thelma invests $ 40,000 in a long-term CD that pays 5 percent interest, compounded annually, what will be the approximate total value of the investment when Thelma is ready to retire 42 years later?