Answer to Question #151191 in Calculus for minal sher

Question

if one student from group.B comes to group.A their strength becomes equal but if one student from group.A comes to group.B the strength of group B becomes double . How many students are present in both groups?

Answer 1

Solution:

Given that "There are two student groups. They are Group A and Group B."

Let the number of students in group A be x and number of students in group B be y.

There are two conditions given:

(I) If one student from group B comes to group A their strength becomes equal.

⇒ x +1 = y - 1

⇒ x - y = -2 .......................................(i)

(II) If one students from group A comes to group B, the strength of group B becomes double.

⇒ 2(x -1) = y + 1

⇒ 2x - 2 = y + 1

⇒ 2x - y = 3........................................(ii)

Now we substract equation (ii) from (i), we get

⇒ x - y-(2x - y) = - 2-(3)

⇒ x - y - 2x + y = -2-3

⇒ - x = - 5

⇒ x = 5

Substitute x = 5 into equation (i), we get

⇒ x - y = - 2

⇒ 5 - y = - 2

⇒ - y = - 2 - 5

⇒ - y = - 7

⇒ y = 7

Therefore,

Number of students present in group A = 5 and

Number of students present in group B = 7