A few weeks ago I put some petrol in and my first try to start the car just gave a skreeching noise

Started ok on second attempt.
Today however My Lude wouldn't start just made the same noise

After about 10 atempts it sluggishly started and then just managed to pick up and run.
I thought it may be the battery as the car wasn't driven over the weekend but battery seems fine all dash lights are bright and battery indicator is green on battery body so I'm guessing it might be the starter motor

How long do they normally last


Cheers for your help peops

Toadster