Dear CD

I thank you on Banwari's behalf for the kind words. I am sure Ban, as Banwari is known as in the office, will be blushing!

Now regarding your query. It is not advisable to have tyres of different dimensions. In your case, the aspect ratio of the two tyres differ. Aspect ratio is basically the percentage value of the section height wrt section width. This will hamper the dynamics of the car. The tyres may wear out sooner than expected and the allignment may suffer as well. It will also have a negative impact on the steering. Just look at it this way - you are standing on a staricase. One foot of yours is on a raised platform while the other is on lower one. How will it feel? This tyre problem is similar. The section height of the two tyres are different here. Please change it to the same ratings.

Hope this helps.

Ashish has explained it very nicely, you should not use such a combination.

Maybe the previous owner must have had a spare tyre so must have used it.

Well, I recommend you to get the tyres replaced immediately if you haven't done it yet. In your case there might be a tyre which would be wearing away very rapidly and that can burst anytime and its a great risk to drive a car that way. Regarding the reason why the previous owner has kept it, he must have sold the original tyres at a good price and then while selling you the car, must have replaced with low quality used tyres which you should have checked while purchasing the car.