|6. Talking about his neighbours, Ram says: "A is 5 times as old as B but his age is||7||of C's age.|
Answer: c. 83 years
A's age = 5 times B's = 5B years
|Also, A's age||=||7||of C's age|
|∴ C's age||=||18||of A's age =||18||x 5B =||90B||years|
|∴ 5B + B +||90B||= 132 years|
|C's age =||90B||= 90 years|
Answer: d. 40 years
Present average age of the group = 36 years
Sum of present ages of all 4 children in the group = 36 x 4 = 144 years.
The youngest child is 6 years old, which means, the youngest was born 6 years ago.
So now, 6 years ago,
Sum of ages of all 4 children = 144 - (6 x 4) = 144 - 24 = 120 years
Since youngest one was just born, his age was 0.
So, now we should not include the youngest child in the group
So now, total number of children = 4-1=3
|Average age of group at time birth of the youngest child||=||Sum of ages of children|
|Number of children|
|∴ Average age of group at time birth of the youngest child||=||120||= 40 years|
Answer: c. 3 years
4 years back,
Average age of family = 19 years
Sum or Total of all ages of all 4 family members = 19 x 4 = 76 years
In present day, that means after 4 years,
Sum or Total of present ages of these 4 family members = 76 + (4 x 4) = 92 years.
Let the child's present age be K years.
Now family is of 5 members (because a child has been added some years back)
|Present average age of family||=||Sum of present ages of 4 members + Child's present age|
Answer: d. 36 years
Answer: a. 35 years and 32 years