Asap
find how long it takes $1500 to double if it is invested at 7% interest compound semiannually. use the formula a=p (1+r/n)^nt to solve the compound interest problem.
it will take approximately how many years ?
round to the nearest tenth as needed.

A=future amount
P=present amount
r=rate in decimal
n=number of times per year compounded
t=time in years

how many years to double
basically
A=2P at t=?
so we can simplify and ignore the pricipal given and do

r=7%=0.07
n=2 (semiannualy means 2 times per year)
t=t




take the ln of both sides

divide both sides by ln1.035

times 2 both sides

use calculator
40.2976=t
nearest tenth
40.3
about 40.3 years

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.