EASY
9th ICSE
IMPORTANT
Earn 100

Find the mean of the first seven odd prime numbers.

Important Questions on Statistics

EASY
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 6
The marks (out of 100) obtained by a group of students in a Mathematics test are 81,72,90,90,85,86,70,93 and 71. Find the mean marks obtained by the group of students.
EASY
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 6
The mean of the age of three students Vijay, Rahul and Rakhi is 15 years. If their ages are in the ratio 4:5:6 respectively, then find their ages.
MEDIUM
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 7
The mean of 5 numbers is 20. If one number is excluded, mean of the remaining numbers becomes 23. Find the excluded number.
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9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 8
The mean of 25 observation is 27. If one observation is included, the mean still remains 27. Find the included observation.
MEDIUM
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 9

The mean of 5 observation is 15. If the mean of the first three observations is 14 and that of the last three is 17, find the third observation.

EASY
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 10
The mean of 8 variates is 10.5. if seven of them are 3,15,7,19,2,17 and  8, then find the 8th variate.
MEDIUM
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 11
The mean weight of 8 students is 45.5 kg. Two more students having weights 41.7kg and 53.3kg join the group. What is the new mean weight?
EASY
9th ICSE
IMPORTANT
Understanding ICSE Mathematics Class 9>Chapter 20 - Statistics>EXERCISE 20.1>Q 12
Mean of 9 observations was found to be 35. Later on , it was detected that an observation 81 was misread as 18. Find the correct mean of the observations.