Advertisements
Advertisements
प्रश्न
If the mean of 1, 2, 3, …, n is `(6"n")/11`, then the value of n is
विकल्प
10
12
11
13
Advertisements
उत्तर
11
Explanation:
The mean of 1, 2, 3, …., n is `(6"n")/11`
i.e., `(1 + 2 + 3 + 4 + ... + "n")/"n" = (6"n")/11`
`(("n"("n" + 1))/2)/"n" = (6"n")/11`
`("n" + 1)/2 = (6"n")/11`
11 (n + 1) = 2 × 6n
11n + 11 = 12n
∴ n = 11
APPEARS IN
संबंधित प्रश्न
The monthly incomes of 8 families in rupees in a certain locality are given below. Calculate the mean, the geometric mean and the harmonic mean and confirm that the relations among them holds true. Verify their relationships among averages.
| Family: | A | B | C | D | E | F | G | H |
| Income (Rs.): | 70 | 10 | 50 | 75 | 8 | 25 | 8 | 42 |
A man travelled by car for 3 days. He covered 480 km each day. On the first day, he drove for 10 hours at 48 km an hour. On the second day, he drove for 12 hours at 40 km an hour and for the last day he drove for 15 hours at 32 km. What is his average speed?
Calculate AM, GM and HM from the following data and also find its relationship:
| Marks: | 0 - 10 | 10 - 20 | 20 - 30 | 30 - 40 | 40 - 50 | 50 - 60 |
| No. of students: | 5 | 10 | 25 | 30 | 20 | 10 |
When an observation in the data is zero, then its geometric mean is __________.
The best measure of central tendency is _________.
Median is the same as:
Find out the GM for the following.
| Yield of Rice (tones) | No. of farms |
| 7.5 - 10.5 | 5 |
| 10.5 - 13.5 | 9 |
| 13.5 - 16.5 | 19 |
| 16.5 - 19.5 | 23 |
| 19.5 - 22.5 | 7 |
| 22.5 - 25.5 | 4 |
| 25.5 - 28.5 | 1 |
Define the mean.
Which type of average is defined as the value repeated the maximum number of times in a dataset?
If each value in a dataset is increased by the same constant, what happens to the mean and median?
