how do I work this problem simple intrest

I=Prt
P= $54 r=4% and t=9months

I = 54 * 0.04 * 0.75

I did this and got 1.62 am I suppose to just end there or divide by another

That's the problem. That's the end of it. You've multiplied P*r*t, what else is left to do?

The interest is $1.62.

I don't mean to be difficult that's what I had also the computer kept saying I was wrong. Sorry for asking

I understand the formula given is to calculate interest, but does the question ask to calculate interest or amount owing?

To calculate simple interest, you can use the formula:

I = P * r * t

Let's plug in the given values:

P = $54 (the principal amount)
r = 4% (the interest rate)
t = 9 months (the time period)

Now, we'll substitute these values into the formula:

I = $54 * 0.04 * 9

To simplify, we can first convert the percentage to decimal form by dividing it by 100:

I = $54 * 0.04 * 9 = $54 * 0.36

Now, multiply the principal amount ($54) by 0.36 to calculate the simple interest:

I = $19.44

Therefore, the simple interest on a principal amount of $54, with an interest rate of 4% over a period of 9 months, is $19.44.