When Ravi was born, his mother's age was 26 yr and his elder brother was 3 year elder to him mother's age when brother was born = 26 - 3 = 23 year Ravi's father was 28 yr of age when his sister was born and his sister was 4 yr of age when his brother was born. ∴ Age of father when brother was born = 28 + 4 = 32 yr.