Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
Mean weight of 120 students = 52.75 kg
⇒ Sum of the weight of 120 students = 120 x 52.75 = 6330 kg
Mean weight of 50 students = 51 kg
⇒ Sum of the weight of 50 students = 50 x 51 = 2550 kg
⇒ Sum of the weight of remaining ( 120 - 50 ) = 70 students
= Sum of the weight of 120 students - Sum of the weight of 50 students
= ( 6330 - 2550 ) kg
= 3780 kg
⇒ Mean weight of remaining 70 students = `3780/70` = 54 kg.
APPEARS IN
संबंधित प्रश्न
Find the mean of the first six natural numbers.
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 x if 9, x, 14, 18 x, x, 8, 10 and 4 have a mean of 11.
Find the mean of 75 numbers, if the mean of 45 of them is 18 and the mean of the remaining ones is 13.
The mean of 200 items was 50. Later on, it was discovered that two items were misread as 92 and 8 instead of 192 and 88.
Find the correct mean.
If different values of variable x are 9.8, 5.4, 3.7, 1.7, 1.8, 2.6, 2.8, 8.6, 10.5 and 11.1;
find
(i) the mean ` barx `
(ii) the value of ` sum (x_i - barx)`
The mean of 5 numbers is 18. If one number is excluded, the mean of the remaining number becomes 16. Find the excluded number.
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.
If `bar"X"` is the mean of n observations x1, x2, x3,..., xn then the mean of `x_1/"a", x_2/"a", x_3/"a",...,x_"n"/"a" "is" bar"X"/"a"`, where a is an non-zero number.
i.e., if each observation is divided by a non-zero number, then the mean is also divided by it.
