Advertisements
Advertisements
Question
If the mean of the following data is 20.2, then find the value of p
| Marks | 10 | 15 | 20 | 25 | 30 |
| No. of students | 6 | 8 | p | 10 | 6 |
Advertisements
Solution
| Marks x |
No. of students f |
fx |
| 10 | 6 | 60 |
| 15 | 8 | 120 |
| 20 | p | 20p |
| 25 | 10 | 250 |
| 30 | 6 | 180 |
| `sumf` = 30 + p | `sumfx` = 610 + 20p |
`bar(x) = (sumfx)/(sumf)`
20.2 = `(610 + 20"p")/(30 + "p")`
610 + 20 p = 20.2 ...(30 + p)
610 + 20 p = 606 + 20.2 p
610 – 606 = 20.2 p – 20 p
4 = 0.2 p
p = `4/0.2`
= `(4 xx 10)/2`
= 20
The value of p = 20
APPEARS IN
RELATED QUESTIONS
Following table shows the points of each player scored in four games:
| Player | Game 1 | Game 2 | Game 3 | Game 4 |
| A | 14 | 16 | 10 | 10 |
| B | 0 | 8 | 6 | 4 |
| C | 8 | 11 | Did not play | 13 |
Now answer the following questions:
- Find the mean to determine A’s average number of points scored per game.
- To find the mean number of points per game for C, would you divide the total points by 3 or by 4? Why?
- B played in all the four games. How would you find the mean?
- Who is the best performer?
In a research laboratory scientists treated 6 mice with lung cancer using natural medicine. Ten days later, they measured the volume of the tumor in each mouse and given the results in the table
| Mouse marking | 1 | 2 | 3 | 4 | 5 | 6 |
| Tumor Volume (mm3) | 145 | 148 | 142 | 141 | 139 | 140 |
Find the mean
The algebraic sum of the deviations of a set of n values from their mean is
The mean of 5, 9, x, 17 and 21 is 13, then find the value of x
The marks of 14 students in a science test out of 50 are given below. 34, 23, 10, 45, 44, 47, 35, 37, 41, 30, 28, 32, 45, 39 Find the minimum mark obtained
Find the mean of first 10 prime numbers and first 10 composite numbers
The mean of three numbers is 40. All the three numbers are different natural numbers. If lowest is 19, what could be highest possible number of remaining two numbers?
The mean of a data is defined as ______.
The mean of three numbers is 10. The mean of other four numbers is 12. Find the mean of all the numbers.
In a class of 100 students there are 70 boys whose average marks in a subject are 75. If the average marks of the complete class is 72, then what is the average of the girls?
