Advertisements
Advertisements
प्रश्न
The distribution X and Y with total number of observations 36 and 64, and mean 4 and 3 respectively are combined. What is the mean of the resulting distribution X + Y?
उत्तर
According to the question,
4 =`X/36 and 3 = Y/64`
⟹ 𝑋 = 4×36 𝑎𝑛𝑑 𝑌 = 3×64
⟹ 𝑋 = 144 𝑎𝑛𝑑 𝑌 = 192
𝑁𝑜𝑤, 𝑋 + 𝑌 = 144 + 192 = 336
And total number of observations = 36 + 64 = 100
Thus, mean =`336/100= 3.36.`
APPEARS IN
संबंधित प्रश्न
What do you understand by the word “statistics” in
(i) Singular form
(ii) Plural form?
Describe some fundamental characteristics of statistics.
What is primary data?
What secondary data?
Which of the two – the primary or the secondary data – is more reliable and why?
Explain the meaning of the term Class-size.
Explain the meaning of the term Class limits.
Define cumulative frequency distribution.
Explain the difference between a frequency distribution and a cumulative frequency distribution.
Find the mean, median and mode of the following data:
| Class | 0 – 10 | 10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 | 50 – 60 | 60 – 70 |
| Frequency | 4 | 4 | 7 | 10 | 12 | 8 | 5 |
Find the mean, median and mode of the following data:
| Class | 0 – 50 | 50 – 100 | 100 – 150 | 150 – 200 | 200 – 250 | 250 – 300 | 300 - 350 |
| Frequency | 2 | 3 | 5 | 6 | 5 | 3 | 1 |
For a certain distribution, mode and median were found to be 1000 and 1250 respectively. Find mean for this distribution using an empirical relation.
While calculating the mean of a given data by the assumed-mean method, the following
values were obtained.
`A=25, sum f_i d_i=110, sum f_i= 50`
Find the mean.
The median of 19 observations is 30. Two more observation are made and the values of these are 8 and 32. Find the median of the 21 observations taken together.
Hint Since 8 is less than 30 and 32 is more than 30, so the value of median (middle value) remains unchanged.
In the following data, find the values of p and q. Also, find the median class and modal class.
| Class | Frequency (f) | Cumulative frequency (cf) |
| 100 – 200 | 11 | 11 |
| 200 – 300 | 12 | p |
| 300 – 400 | 10 | 33 |
| 400- 500 | Q | 46 |
| 500 – 600 | 20 | 66 |
| 600 – 700 | 14 | 80 |
Find the class marks of classes 10−25 and 35−55.
Explain the meaning of the following terms: True Class Limits
Can the experimental probability of an event be a negative number? If not, why?
The monthly pocket money of ten friends is given below :
₹ 80, ₹ 65, ₹ 35, ₹ 65, ₹ 50, ₹ 30, ₹ 60, ₹ 35, ₹ 65, ₹ 30
What is the highest pocket money?
