Then1-110 = 9/10 is the number of people who subscribe to Math Newspaper, Pupils Weekly and these two newspapers.

The number of subscribers of 3/5+3/4=27/20 has doubled. Because of the two newspapers, 3/5 subscribes to the weekly newspaper, so 3/5+3/4 also subscribes to the mathematical newspaper, so 3/5+3/4 should have been equal to 9/ 10, but the number of subscribers has doubled.

So 3/5+3/4-9/ 10=9/20.