Advertisements
Advertisements
प्रश्न
The mean of x, x + 2, x + 4, x + 6 and x + 8 is 11, find the mean of the first three observations.
उत्तर
Let `barx` be the mean of n number of observation x1, x2, x3, ...., xn.
Mean = `[ x_1 + x_2 + x_3 + ......... + x_n ]/n`
Therefore,
Mean of given data
= `[ x + x + 2 + x + 4 + x + 6 + x + 8 ]/5`
= `[ 5x + 20 ]/5`
= x + 4
Also, it's given that mean of the given data is 11.
⇒ x + 4 = 11
⇒ x = 7
Hence the mean of the first three observation = `[ x + x + 2 + x + 4 ]/3`
= `[3x + 6]/3`
= x + 2
= 7 + 2
= 9.
APPEARS IN
संबंधित प्रश्न
The mean of 15 observations is 32. Find the resulting mean, if the observation is: Decreased by 7
Find the mean of 8, 12, 16, 22, 10 and 4. Find the resulting mean, if the observations, given above, be: multiplied by 3 and then divided by 2.
Find the median of: 25, 16, 26, 16, 32, 31, 19, 28 and 35
Find the mean of 8, 12, 16, 22, 10 and 4. Find the resulting mean, if each of the observations, given above, be: decreased by 40%
The mean weight of 60 students in a class is 40 kg. The mean weight of boys is 50 kg while that of girls is 30 kg. Find the number of boys and girls in the class.
Find the mean and median of all the positive factors of 72.
The weight of the seven members of a family, in kilograms are given below:
20, 52, 56, 72, 64, 13, 80.
Find mean weight.
The marks obtained by 10 students are listed below:
2, 5, 3, 8, 0, 9, x, 6, 1, 8
If the mean marks is 5, find x.
A test out of 25 marks was given to 16 students and marks scored are recorded below:
25, 8, 14, 20, 16, 22, 10, 15, 8, 7, 24, 18, 19, 6, 11, 14
Find the mean marks
A test out of 25 marks was given to 16 students and marks scored are recorded below: 25, 8, 14, 20, 16, 22, 10, 15, 8, 7, 24, 18, 19, 6, 11, 14
In the report, marks were entered out of 50. What is the mean of the recorded marks in the report?