There were 2 new admissions to Sudhakar’s class just a couple of days after the class average height was found to be 150.2 cm. Class 8

There were 2 new admissions to Sudhakar’s class just a couple of days after the class average height was found to be 150.2 cm. Class 8

Question 1.

There were 2 new admissions to Sudhakar’s class just a couple of days after the class average height was found to be 150.2 cm. Class 8

(i) Which of the following statements are correct? Why?

(a) The average height of the class will increase as there are 2 new values.

(b) The average height of the class will remain the same.

(c) The heights of the new students have to be measured to find out the new average height.

(d) The heights of everyone in the class has to be measured again to calculate the new average height.

(ii) The heights of the two new joinees are 149 cm and 152 cm.

Which of the following statements about the class’ average height are correct? Why?

(a) The average will remain the same.

(b) The average will increase.

(c) The average will decrease.

(d) The information is not sufficient to make a claim about the average.

(iii) Which of the following statements about the new class average height are correct? Why?

(a) The median will remain the same.

(b) The median will increase.

(c) The median will decrease.

(d) The information is not sufficient to make a claim about median.

Solution:

(i) (a) Not correct. It will depend upon the heights of new students.

(b) Not correct. It will depend upon the heights of new students.

(c) Correct.

(d) Not correct.

(ii) (a) Not correct, because [latex]\frac{149+152}{2}[/latex] not equal to 150.2.

(b) Correct, because [latex]\frac{149+152}{2}[/latex] > 150.2.

(c) Not correct, because [latex]\frac{149+152}{2}[/latex] > 150.2.

(d) Not correct.

(iii) (a) Not correct.

(b) Not correct

(c) Not correct

(d) Correct.