If class-mark is 10 and class width is 6, then find the class.

6 views

1 Answers

Let the upper class limit be x and the lower class limit be y.

 Class mark = 10 …[Given] 

Class-mark

\(\cfrac{Lowr\, class\, Limit\,+\,Upper\, Class\,Limit}{2}\) 

\(10=\frac{x+y}{2}\)

= x + y =20...

Class width = 6 … [Given] 

Class width = Upper class limit – Lower class limit 

∴ x – y = 6 …(ii) 

Adding equations (i) and (ii),

 x + y = 20

 x – y = 6

2x = 26

∴ x = 13 

Substituting x = 13 in equation (i), 

13 + y = 20

∴ y = 20 – 13 

∴ y = 7 

∴ The required class is 7 – 13.

6 views

Related Questions