-  Let one year ago
Samir’s age be 4X years
And, Ashok’s age be 3X years
Present age of Samir = (4X + 1) years
Present age of Ashok = (3X + 1) years
One year hence
Samir’s age = (4X + 2) years
Ashok’s age = (3X + 1) years
According to question,
  4X + 2 = 5   16 + 8 = 15X + 10   3X + 2 4  
or,       X = 2
Sum of their present ages = 4X + 1 + 3X + 1
= 7X + 2
= 7 x 2 + 2 = 16 years.

If you think the solution is wrong then please provide your own solution below in the comments section .

 -  Let Ram's age = 3X and Mukta's age = 5X
  3X + 9 = 3       4 (3X + 9) = 3 (5X + 9) 5X + 9 4
Mukta's age = 15 years.

Let's assume that the present age of Mukta is 5x years.

Then, the present age of Ram will be 3x years.

After 9 years, the age of Mukta will become 5x + 9 years, and the age of Ram will become 3x + 9 years.

The given ratio of their ages after 9 years is 3 : 4. Hence,

(3x + 9) / (5x + 9) = 3/4

Cross-multiplying, we get:

12x + 108 = 15x + 135

Solving for x, we get:

3x = 27

Hence, x = 9.

Therefore, the present age of Mukta is 5x = 5 * 9 = 45 years.

To summarize:

The present age of Mukta is 45 years.

Answer: A - 15.

If you think the solution is wrong then please provide your own solution below in the comments section .

 -     Difference Total
50 Students
(22 Years) - 2 =>
10 (26 Years) + 2 =>
30(?) -20
+20
Observe that 10 students have an average of 22 years (2 years below 24). While another 10 students
have an average of 26 years (2 years above 24). Thus, the effect by (-2) is nullified by the effect of
(+2).As such, the average of remaining 30 students would remain same as 24 years.

Let the average age of the remaining 30 students be x.

We know that the average age of the entire class of 50 students is 24 years. Therefore, the total age of all the students is:

50 * 24 = 1200 years

We also know that the average age of 10 of the students is 22 years. Therefore, the total age of these 10 students is:

10 * 22 = 220 years

Similarly, the total age of the other 10 students whose average age is 26 years is:

10 * 26 = 260 years

Now, let's use the formula for the average:

Average = (Sum of values) / (Number of values)

We can use this formula to find the total age of the remaining 30 students:

Total age of remaining 30 students = (50 * 24) - 220 - 260

Total age of remaining 30 students = 1200 - 480

Total age of remaining 30 students = 720

Therefore, the average age of the remaining 30 students is:

Average age of remaining 30 students = Total age of remaining 30 students / Number of remaining students

Average age of remaining 30 students = 720 / 30

Average age of remaining 30 students = 24

Hence, the correct answer is option B, which is 24 years.

If you think the solution is wrong then please provide your own solution below in the comments section .

 -  Let Mr. Sohanlal’s age (in years) = X and his son’s age =Y
Then, X – 5 = 3(Y – 5) i.e. X – 3Y + 10 = 0
And, X + 10 = 2 (Y + 10) i.e. X – 2Y – 10 = 0
Solving the two equations, we get
X = 50, Y = 20.

Let Mr. Sohanlal's present age be x years and his son's present age be y years.
Then, according to the given information, five years ago,

x - 5 = 3(y - 5)
=> x - 5 = 3y - 15
=> x = 3y - 10

Also, ten years hence,

x + 10 = 2(y + 10)
=> x + 10 = 2y + 20
=> x = 2y + 10

Substituting the value of x from equation (1) in equation (2),

3y - 10 = 2y + 10
=> y = 20

Hence, Mr. Sohanlal's present age = 3 × 20 = 50 years

Therefore, the correct answer is Option D. 50 years.

 -  Avg x Number = Total
30 nos x 21 years = 630 years                   …..(1)
30 nos x 22 years = 682 years                   …..(2)
Teacher's age = (2) - (1) = 682 - 630 = 52 years.

Average is the sum of all the values divided by the number of values.

Therefore, the average of the 30 students (without the teacher) = 21

Let 'x' be the teacher's age.

Therefore, the average of the 30 students (including the teacher) = 21 + 1 = 22

Formula for Average:
Average = Sum of all values/ Number of values

Therefore,
22 = (30×21 + x)/31

On solving the above equation,
x = 31×22 - 30×21
= 682 - 630
= 52

Hence, the teacher's age is 52 years.

Therefore, the correct option is option D: 52 years.