The average age of a family with 5 members is 28. If one of the 5 members of age 20 is excluded the average age of the family becomes -

Answer: Option C

Total age of 5 members = 5 × 28 = 140
And, required average
= $$\frac{140-20}{4}$$
= $$\frac{120}{4}$$
= 30 years