Kirk inherited some money from his grandfather and put it in a bank account that earns 3% interest compounded quarterly. After 10 years, Kirk had 500.00 in the bank account. How much interest did he earn?

الحلّ

K i r k inh er i t e d so m e m o n ey f ro m hi s g r an df a t h er an d p u t i t in a bank a cco u n t t ha t e a r n s 3% in t eres t co m p o u n d e d q u a r t er l y . A f t er 10 ye a rs, K i r k ha d 500.00 in t h e bank a cco u n t . Ho w m u c h in t eres t d i d h e e a r n ?

Interest : 129.18

خطوات الحلّ

Translate the problem into an equation:

500 = 370.82398 \dots + I

500 = 370.82398 \dots + I, I

حلّ لـ:

I = 129.18

Interest : 129.18