Read the information carefully and answer the questions given below:

Seven persons A, B, C, D, E, F and G were born on seven different years i.e., 1947, 1959, 1964, 1973, 1978, 1988 and 2001 on the same month and same date. (Base year is considered as 2025 for age calculation). The sum of the ages of C and F is equal to the age of D. G’s age is divisible by 6. The total age of A and G is a prime number. A is just older than F. The sum of the age of B and A is divisible by 5.

What is the difference between the age of C and D?

Correct Answer: 37 years

Let us find the ages of the seven persons based on their birth years with the base year set as 2025:
1. Born in 1947: $2025-1947=78$ years
2. Born in 1959: $2025-1959=66$ years
3. Born in 1964: $2025-1964=61$ years
4. Born in 1973: $2025-1973=52$ years
5. Born in 1978: $2025-1978=47$ years
6. Born in 1988: $2025-1988=37$ years
7. Born in 2001: $2025-2001=24$ years
So, the set of calculated ages in descending order is: {78, 66, 61, 52, 47, 37, 24}.

Now, we apply the given clues to determine the age of each person step-by-step:

Step 1: Determine the ages of C, F, and D.
We are given that the sum of the ages of C and F is equal to the age of D ($C+F=D$).
Looking at the available set of ages, the only combination of two ages that sums up to another age in the list is:
$24+37=61$
Therefore, D's age must be 61 years, and the ages of C and F must be 24 and 37 in some order.

Step 2: Use the clue "A is just older than F" to find the exact ages of A, F, and C.
"Just older than" means A was born in the year immediately preceding F's birth year.
Let us analyze the two cases for F:
- If F's age is 24 (born in 2001), then the person born immediately before F would be born in 1988 (age 37). This would make A's age 37. However, this causes a conflict because C's age would then also have to be 37 (since C and F are 24 and 37).
- If F's age is 37 (born in 1988), then the person born immediately before F would be born in 1978 (age 47). This means A's age is 47. Since F's age is 37, C's age is 24. This satisfies all conditions without any conflict.
Thus, we have: A = 47, F = 37, C = 24, and D = 61.

Step 3: Determine the age of G.
We are given that G's age is divisible by 6.
From the list of ages, the numbers divisible by 6 are 78, 66, and 24. Since 24 is already assigned to C, G's age can be either 78 or 66.
We are also given that the total age of A and G is a prime number.
- If G = 78, then $A+G=47+78=125$, which is not a prime number.
- If G = 66, then $A+G=47+66=113$, which is a prime number.
Therefore, G's age is 66 years.

Step 4: Determine the remaining ages.
The remaining ages to be assigned to B and E are 78 and 52.
We are given that the sum of the ages of B and A is divisible by 5.
- If B = 78, then $B+A=78+47=125$, which is divisible by 5.
- If B = 52, then $B+A=52+47=99$, which is not divisible by 5.
Thus, B's age is 78 years, and E's age is 52 years.

Step 5: Calculate the difference between the age of C and D.
The age of C is 24 years and the age of D is 61 years.
The difference between their ages is:
$D-C=61-24=37$ years.