I bought my P21500 new from the dealer in 1994.
I do not know what year my model 917.270930 lawn mower was built
It was made in late 2001 for the 2002 model year
1974
1998
1998
1995
That would depend on what sort/make/model of mower it was and what country it was made (and possibly sold) in.
2001
On a Arien's mower you will use 46 inch belt. This is an older type lawn mower.
1998
Your question is not clear and very confusing. Please ask again and this time list make, model, and year of the mower your are referring to.
1980