What is the Correct Way to Calculate Average Force of Impulse?

[Psych Berry]

I can't seem to master this equation, because I think I'm doing things right and I'm not.

Homework Statement

When a 410 baseball gram is hit, its velocity changes from +28.87 m/s to -22.34 m/s. The baseball is in contact with the bat for 56.10 milliseconds. You may assume that the balls outward velocity is antiparallel to its incoming velocity.

What is the magnitude of the average force on the ball?

Homework Equations

FΔt = mΔv

The Attempt at a Solution

(0.410 kg)(-22.34 m/s - 28.87 m/s)/(0.0561 s) = F
374.3 N = F
But this isn't correct.

I messed up Δv before, did I do it again?

 

[Doc Al]

Looks OK to me. Why do you say it's wrong?

 

[Psych Berry]

Looks OK to me. Why do you say it's wrong?

It's an online pre-assignment, said my answer was incorrect. I tried playing around with sig figs and signs (in case the question forgot it's supposed to be magnitude), but I've tried 5 times and haven't been able to get it correct.

 

[Doc Al]

Those online systems can be flaky. But there's nothing wrong with your understanding of that impulse-momentum equation.

 

[Psych Berry]

Those online systems can be flaky. But there's nothing wrong with your understanding of that impulse-momentum equation.

That's definitely true, thanks! I for sure trust your physics judgment over the program's.