Question 1139234
P=Po(1+.10/3)^3n, where n is the number of years.
Rule of 70 would suggest about 7 years.
P=2Po for doubling
so 2=(1+.03333)^3n.
take ln both sides
ln2=3n ln(1.03333)
3n=21.139, dividing ln2 by ln 1.0333 
n=7.046 years.