t is 10 yrs * 4 qtrs per year = 40
40 = ln(2) / ln(1 + r)
ln(2) / 40 = ln(1 + r)
0.69315 / 40 = ln(1 + r)
0.01733 = ln(1 + r)
e^0.01733 = 1 + r
1.01748 = 1 + r
r = 0.01748
0.01748 * 4 = 0.06992
7% will generate $1000.80 in 10 years. I wish I could work out the formula for you. My infotr comes from bankrate.com. I tried working it myself and could not figure it out. I even tried reversing it and still could not get it already knowing the answer.
This is basic algebra. To solve you take logarithmic of both sides. Duh
1. Stephen has $500 to invest. What annual interest rate compounded quarterly is required to double his money in 10 years?
*This is my work but for some reason I'm having a hard time isolating the r*
A= P (1+r/m)^mt
1000=500 (1+r/4)^4(10)
2=(1+r/4)^40
2. A(t)=Ae^-0.037t. Find the half life of, t when there is half as much as what was originally there.
Please show work. Thanks in advance.
