I don’t understand simple and compound interest

Question

Can someone help me know the difference between simple and compound interest? Here is a question I need help on.

Write the equations for a savings account with an initial deposit of $10,000 at a 1.8% interest rate

a. Simple interest:

Compound interest:

b. How long will it take for the money to double using compound interest?

Answer 1

a) I = prt, I = 10,000(.018)t. Time was not given in this problem. = simple interest

b) A = P(1 + r)^t = 10,000(1 + .018)^t = compound interest

= 10,000(1.018)^t

c) t = 39 years

d) A - 10,000(1.018)^39 = 10,000(2.00522606897)

= 20,052.26069

= about $20,052 in 39 years. In doubles in 39 years.

I hope this helps!