Advertisements
Advertisements
प्रश्न
Find the mean of 75 numbers, if the mean of 45 of them is 18 and the mean of the remaining ones is 13.
उत्तर
Mean of 45 numbers = 18
⇒ Sum of 45 numbers = 18 x 45 = 810
Mean of remaining ( 75 - 45 ) 30 numbers = 13
⇒ Sum of remaining 30 numbers = 13 x 30 = 390
⇒ Sum of all the 75 numbers = 810 + 390 = 1200
⇒ Mean of all the 75 numbers = `1200/75` = 16
APPEARS IN
संबंधित प्रश्न
Find the mean of 43, 51, 50, 57 and 54.
Find the mean of all factors of 10.
Find x if 9, x, 14, 18 x, x, 8, 10 and 4 have a mean of 11.
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.
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.
The mean of 5 numbers is 18. If one number is excluded, the mean of the remaining number becomes 16. Find the excluded number.
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.
