Question

In a class, average height of all students is 'p' cm. Among them, average height of
10 students is 'q' cm and the average height of the remaining students is 'r' cm.
Eind the number of students in the class. (Here P>r and q> r)
(A P(q-r)/(p=r)
AB) (q=r)/(p-1)
(C) (q=r)/10(p-r)
(D) 10(q=r)/(p-r) 7​

Answer 1

Answer:

Step-by-step explanation:

xa = total number of students in a class

10b = average height of 10 students

(x- 10)c = average height of remaining students

=>

xa =10b +(x-10)c

xa =10b + xc-10c

xa- xc =10b-10c

x(a-c)=10(b-c)

x=10(b-c)/(a-c)

Ans.x=10(b-c)/(a-c)