Keisha's parents want to save twenty thousand dollars in her college savings account over the next twenty years. They have eight thousand dollars to use as an initial deposit. What simple annual interest rate do they need to meet their goal? Round your answer to the nearest tenth.
Answer

seven point five percent

three point three percent

two percent

nine percent

Question

Keisha's parents want to save twenty thousand dollars in her college savings account over the next twenty years. They have eight thousand dollars to use as an initial deposit. What simple annual interest rate do they need to meet their goal? Round your answer to the nearest tenth.
Answer
		
seven point five percent
		
three point three percent
		
two percent
		
nine percent

ash2326 · Answer

We want Principle+Interest>=$20000
Principle=$8000
Let Rate  be R %
Time =20 years
so
$$8000+(8000*R*20)/100\ge20000$$
or
$$8000+1600R\ge20000$$
or
$$1600R\ge12000$$
or
$$R\ge7.5$$
so
R=7.5 %
option A

anonymous · Answer

oh! i see thanks :D