Jessica deposits $6509 in bank at r% p.a. compounded half-yearly. If she obtains an amount of $6764 after 1 year, find the value of r.
6509(1+r)^2 = 6764 , where r is the semi-annual rate
(1+r)^2 = 1.03176...
take √ of both sides
1+r = 1.0194
r = .0194 = 1.94% per half-year
so the annual rate compounded semi-annually is 3.88%