Question 1035349
Let the entire no. Of people surveyed be x.

Total no. Of no opinion = 15% * x = (5+20+5)
Or, 15/100 * x = 30
Therefore, x= 200.

Now, let y be the no. Of people of age group 21-40 years who were surveyed.

Therefore 40% * y = 20
Therefore y = 50

No. of (For + against + no opinion) of 21-40 years age group = 50 
Or, for + 20 + 5 = 50
1. For = 25 in age group 21-40 years.

Now, total no. Of all people = 200
No. of people in (Age Grp 21-40 + age Grp 41-60 + over 60) = 200.
Or, (50)+( 20+against+ 20)+(55 +15+ 5) = 200
Therefore, no. Of people against increase in age group 41-60 = 35.