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The ages of father, mother and son are in the ratio 4 ∶ 3 ∶ 1. Daughter’s age is 2/5th of mother’s age and grandmother’s age is twice that of mother’ age. The average age of the family of five members is 45.6. Find the age of grandmother.
- A70 years
- B80 years
- C90 years
- D100 years
Answer not set