Class IX Math NCERT Solution for Statistics 14.1

EXERCISE: 14.1
1.   Give five examples of data that you can collect from your day-to-day life.
Sol. Following are five examples which are related to day-to-day life.
        (i) Number of girl students in our class.
        (ii) Number of computer sets in our computer-lab.
        (iii) Telephone bills of our house for last two years.
        (iv) Number of students appeared in an examination, obtained from newspapers.
        (v) Number of female teachers in all the schools in a state obtained from the education department.
2.   Classify the data in Q. 1 above as primary or secondary data.
Sol. We have:
        Primary data: (i), (ii) and (iii)
        Secondary data: (iv) and (v)

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