Celo used the simple interest formula a= p(1+rt) to calculate the interest he earned on his savings last month. which equation is equivalent to the simple interest formula?

Simple interest formula
I=prt
I interest earned
P principle
R interest rate
T time

The second formula
I=A-p
I interest earned
A future value
P principle

Lets solve your question now
A=p (1+rt)
A= p+prt. ((As you can see prt is the formula of the simple interest which is I=prt))
So the equation turn to be
A=p+I. Subtract p from both sides to get

I=A-p answer

Hope it helps