Katie has $7 in a savings account. The interest rate is 5%, compounded annually.
To the nearest cent, how much interest will she earn in 3 years?

Compound interest earned would be $1.1034

Step-by-step explanation:

The formula for amount, when interest is compounded annually is

A = P(1+r)^n

Here

A= amount

P= principal

r= rate of interest

n= time period

So putting the values in the formula

A = 7(1+.05)^3

A = 7*(1.05)^3

A = 7*1.157625

A= 8.1034

So the Compound Interest would be

C.I = 8.1034-7.0

C.I = 1.1034

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.