Advertisements
Advertisements
प्रश्न
The mean of 5 numbers is 18. If one number is excluded, the mean of the remaining number becomes 16. Find the excluded number.
Advertisements
उत्तर
Given the mean of 5 numbers is 18
The total sum of 5 numbers
= 18 x 5
= 90
On excluding an observation, the mean of remaining 4 observation is 16
= 16 x 4
= 64
Therefore the sum of the remaining 4 observations
total of 5 observations-total of 4 observations
= 90 - 64
= 26.
APPEARS IN
संबंधित प्रश्न
In a series of tests, A appeared for 8 tests. Each test was marked out of 30 and averages 25. However, while checking his files, A could only find 7 of the 8 tests. For these, he scored 29, 26, 18, 20, 27, 24 and 29.
Determine how many marks he scored for the eighth test.
Find the mean of all factors of 10.
The mean marks (out of 100) of boys and girls in an examination are 70 and 73 respectively. If the mean marks of all the students in that examination are 71,
find the ratio of the number of boys to the number of girls.
The mean weight of 120 students of a school is 52.75 kg. If the mean weight of 50 of them is 51 kg,
find the mean weight of the remaining students.
The mean of 100 observations is 40. It is found that an observation 53 was misread as 83.
Find the correct mean.
If the mean of observations x, x + 2, x + 4, x + 6 and x + 8 is 11,
find:
(i) The value of x;
(ii) The mean of first three observations.
Find the mean of 8, 12, 16, 22, 10 and 4. Find the resulting mean, if the observations, given above, be: divided by 2.
The mean of 16 numbers is 8. If 2 is added to every number, what will be the new mean?
The mean monthly salary of 10 members of a group is Rs.1,445, one more member whose monthly salary is Rs.1,500 has joined the group. Find the mean monthly salary of 11 members of the group.
The mean of 40 observations was 160. It was detected on rechecking that the value of 165 was wrongly copied as 125 for computation of mean. Find the correct mean.
