Question 5 - CBSE Class 10 Sample Paper for 2022 Boards - Maths Standard [Term 2] - Solutions of Sample Papers for Class 10 Boards

Last updated at Jan. 18, 2022 by Teachoo

Mrs. Garg recorded the marks obtained by her students in the following table. She calculated the modal marks of the students of the class as 45. While printing the data, a blank was left. Find the missing frequency in the table given below

Question 5 Mrs. Garg recorded the marks obtained by her students in the following table. She calculated the modal marks of the students of the class as 45. While printing the data, a blank was left. Find the missing frequency in the table given below
Let Missing frequency be x
Given Mode = 45
∴ Modal class is 40 − 50
Mode = l + (𝒇𝟏 −𝒇𝟎)/(𝟐𝒇𝟏 − 𝒇𝟎 − 𝒇𝟐) × h
where l = lower limit of modal class
h = class-interval
f1 = frequency of the modal class
f0 = frequency of the class before modal class
f2 = frequency of the class after modal class
Now,
Mode = l + (𝒇𝟏 −𝒇𝟎)/(𝟐𝒇𝟏 − 𝒇𝟎 − 𝒇𝟐) × h
45 = 40 + (𝑥 − 10)/(2𝑥 − 10 − 6) × 20
45 − 40 = (𝑥 − 10)/(2𝑥 −16) × 20
5 = (𝒙 − 𝟏𝟎)/(𝟐𝒙 −𝟏𝟔) × 20
5(2x − 16) = (x − 10) × 20
10x − 80 = 20x − 200
200 − 80 = 20x − 10x
120 = 10x
10x = 120
x = 120/10
x = 12
Hence, the missing frequency is 12

Made by

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths and Science at Teachoo.