Question

The sum of ages of 5 children born at the intervals of 3 years each is 50 years. What is the age of the youngest child?

• A. 4 years
• B. 5 years
• C. 6 years
• D. 8 years

Hint:

When dealing with age problems involving intervals, express the ages in terms of a variable and form an equation based on the sum or other given information.

Answer 1

The Correct Option is A

Let the age of the youngest child be \( x \). Then the ages of the other children will be \( x + 3 \), \( x + 6 \), \( x + 9 \), and \( x + 12 \), as they are born at intervals of 3 years.
The sum of their ages is: \[ x + (x + 3) + (x + 6) + (x + 9) + (x + 12) = 50 \] Simplifying the equation: \[ 5x + 30 = 50 \] \[ 5x = 50 - 30 \] \[ 5x = 20 \] \[ x = 4 \] Thus, the age of the youngest child is 4 years.

Answer 2

Let the age of the youngest child be x years.
Since each child is born at an interval of 3 years, the ages of the 5 children can be expressed as:
x, x + 3, x + 6, x + 9, x + 12

Step 1: Write the equation for the sum of their ages
Sum of ages = x + (x + 3) + (x + 6) + (x + 9) + (x + 12)
= 5x + (3 + 6 + 9 + 12)
= 5x + 30

Step 2: Use the given total sum of ages
5x + 30 = 50

Step 3: Solve for x
5x = 50 - 30 = 20
x = 4

Conclusion:
The age of the youngest child is 4 years.