The average age of a family of 10 members is 20 years. If the age of the youngest member of the family is 10 years, then the average age of the members of the family just before the birth of the youngest member was approximately.

Question

নিচের অপশন গুলা দেখুন

• 14.28 years
• 12.5 years
• 27.14 years
• $$11\frac{1}{9}$$ years

Answer 1

সঠিক উত্তর হচ্ছে: $$11\frac{1}{9}$$ years

ব্যাখ্যা:

According to the question,
Average age of a family of 10 members is = 20 years
Sum of the age of 10 members
= 20 × 10 = 200 years
If the age of youngest member is = 10 years
Sum of the age of 9 members at the time of birth of youngest member
= 200 - 10 × 10
= 200 - 100
= 100 years
∴ Average of 9 members is
= $$\frac{100}{9}$$ = $$11\frac{1}{9}$$ years