Here you get the NCERT Exemplar Problems and Solutions for CBSE Class 10 Mathematics chapter 13, Statistics and Prbability. This part includes solutions for problems given in exercise 13.2 of class 10 Maths NCERT Exemplar Book. It contains only very short answer type questions framed from various important topics discussed in the chapter. Each question is provided with a detailed yet simple step-wise solution to help students learn the concept and logic working behind that particular question.
NCERT Exemplar problems are a very good resource for preparing the critical questions like Higher Order Thinking Skill (HOTS) questions. All these questions are very important to prepare for CBSE Class 10 Mathematics Board Examination 2017-2018 as well as for other competitive exams.
Few questions from the Class 10 Maths NCERT Exemplar Exercise 13.2 are given below:
Question. 1 The median of an ungrouped data and the median calculated when the same data grouped are always the same. Do you think that this is a correct statement? Give reason.
No, because when we calculate the median of a grouped data, the formula we used is based on the assumption that the observations in the classes are uniformly distributed.
Question. 2 In calculating the mean of grouped data, grouped in classes of equal width, we may use the formula,
Where, a is the assumed mean, a must be one of the mid-point of the classes. Is the last statement correct? Justify your answer.
No, the assumed mean must not always be the mid-point of the class interval. It is considered as any value which may simplify the calculation.
Question. 3 Is it true to say that the mean, mode and median of grouped data will always be different? Justify your answer.
Yes, the mean, mode and median of grouped data will always be different,
As mean = sum of all observations/ number of observations
And mode = The maximum frequency of a particular observation becomes the mode of that particular data
Hence the three measures will always be different.
Question. 4 Will the median class and modal class of grouped data always be different? Justify your answer.
No, the median and modal class of grouped data can also be same in some cases.
Here we have,
N = 50
Then, N/2 = 50/2 = 25
The cumulative frequency just greater than N/2 is 26, then the median class is 120 - 140.
Also the maximum frequency here is 14, then the corresponding class 120 - 140 is the modal class.
Hence the median class and modal class are the same.
To get the solutions to remaining questions of the exercise, visit the following link: