Question

here is my problem, P=3000, A=$3180, t=1 year, how do I find the rate?

Answer 1

the rate of interest?

Answer 2

Is it compound interest or simple interest?

Answer 3

Compound interest:
A=P((100+R)/100)^T
Simple interest:
SI=PRT/100
SI=A-P

Answer 4

You need to solve the equation for rate. I have attached a formula solved for the rate.

Answer 5

Its 6% per annum

Answer 6

The equation is complex and is split into 2 parts.
exp= [log(total/princ)/years]
exp = log(3180/3000)/1
exp = log(1.06)
exp= 0.0253058653

rate = (10^exp -1)
rate = 10^0.0253058653 -1
rate = .06

So, it must be simple interest.
If it were compounded interest you'd definitely need to use the formula.