Question

If a student whose weight is 30 kg was replaced by another student in a class then ,the average weight of 20 student in that class increased by 0.75 kg. Then what is the weight of new student?

Answer 1

Answer:

45 kg

Step-by-step explanation:

Let M1 and M2 be initial and final mean and N be the weight of the new student then

M1=[X1+X2......+X19+30]/20

M2=[X1+X2.....+X19+N]/20

SUBTRACT

M2-M1=(N-30)/20

THUS  N=45 kg

PLEASE MARK AS BRAINLIEST

Answer 2

Answer:

45 kg

Step-by-step explanation:

Let the weight of new student = 'x' kg.

Given that student weight(30 kg) was replaced by another student, then the average weight of 20 students in that class increased by 0.75 kg.

⇒ (x - 30)/20 = 0.75

⇒ x - 30 = 0.75 * 20

⇒ x - 30 = 15

⇒ x = 15 + 30

⇒ x = 45.

Therefore, the weight of new student = 45 kg.

Hope it helps!