8 years ago, the average age of Rahul's family consisting of 6 members was 35 years. One year ago a new baby was born in this family. What will be the average age of the family four years hence?

8 years ago, the average age of Rahul's family consisting of 6 members was 35 years.

8 years ago, the total age of Rahul's family consisting of 6 members = $$35\times6$$ = 210

One year ago, the total age of Rahul's family consisting of 6 members = $$210+7\times6$$ = 210+42 = 252

One year ago a new baby was born in this family.

Present total age of Rahul's family consisting of 7 members = 252+7 = 259 

Four years hence, the total age of Rahul's family consisting of 7 members = $$259+4\times7$$

= 259+28

= 287

Average age of the family four years hence = $$\frac{287}{7}$$ = 41 years