10 times 1 / 11 + 11 times 1 / 12 + +How much is 2000 times 1 / 1999?

10 times 1 / 11 + 11 times 1 / 12 + +How much is 2000 times 1 / 1999?

10 times 1 / 11 + 11 times 1 / 12 + +Two thousand times one in 1999
=1/10-1/11+1/11-1/12+.+1/1999-1/2000
=1/10-1/2000
=199/2000