Direct Method
Trending Questions
The direct method is more accurate than the assumed mean or the step-deviation methods.
True
False
Calculate the mean for the following frequency distribution using direct method.
Class0−1010−2020−3030−4040−5050−6060−70fi68202515104
- 32.4
- 34.2
- 36.4
- 34.6
Find the mean age in years from the frequency distribution given below:
Class interval of age in yearsFrequency(fi)25−29430−341435−392240−441645−49650−54555−593Total70
40.15
39.35
40.39
29.39
The age of the employees in a startup company is shown below. Find the average age of the employees.
AgeNo. of Employees18−263026−347034−425042−503050−581058−6610
- 36
- 34
- 33
- 32
- 2.9
- 3.2
- 3.4
- 3.5
Class Interval0−1010−2020−3030−4040−50Frequency (f)5151023
- 32.7
- 45.8
- 16.5
- 20.1
Find the mean of the following data.
Class0−1010−2020−3030−4040−50Frequency671197
Marks obtainedNumber of students0−10310−20420−301330−401540−505
- 28.75
- 25.25
- 26.44
- 29.91
Question 5 (i)
A study was conducted to find out the concentration of sulphur dioxide in the air in parts per million (ppm) of a certain city. The data obtained for 30 days isas follows:
0.030.080.080.090.040.170.160.050.020.060.180.200.110.080.120.130.220.070.080.010.100.060.090.180.110.070.050.070.010.04
(i) Make a grouped frequency distribution table for this data with class intervals as 0.00 - 0.04, 0.04 - 0.08, and so on.
The distribution of height of 50 children is given. If the mean height for the distribution is 117.8 cm, then complete the following table.
Height110115x1120121125Number of students6814f143
x1=118, f1=15
x1=121, f1=15
x1=118, f1=8
None of these
Variable x12345Frequency of x45Y12
- 24
- 13
- 8
- 3
If the mean of the data is 60, find the value of p
Class intervalfrequency25−351235−451645−55p55−651565−75875−851985−9513 [2 MARKS]
Calculate the mean daily expenditure using direct method.
Daily Expenditure (₹)No. of Persons0−10310−20220−30530−40840−50450−60660−702
- ₹36.3
- ₹39.4
- ₹40.3
- ₹42.8
Calculate the mean daily expenditure using direct method.
Daily Expenditure (₹)No. of Persons0−10310−20220−30530−40840−50450−60660−702
- ₹36.3
- ₹39.4
- ₹40.3
- ₹42.8
Find the mean of the following distribution using assumed mean.
Class Interval100−11010−120120−130130−140140−150Frequency6914219
Find the mean age in years from the frequency distribution given below:
Class interval of age in yearsFrequency(fi)25−29430−341435−392240−441645−49650−54555−593Total70
- 39.36
- 35.39
- 40.15
- 40.39
Class interval of age in yearsFrequency(fi)25−29430−351435−392240−451645−49650−55555−593Total70
- 40.15
- 40.39
- 39.35
- 38.39
∑fx = 5x + 2, ∑f = 12. If the mean of the distribution is 6, what is the value of x?
18
15
14
12
Value:1234Frequency:546f
If the mean is known to be 3, then the value of f is
- 3
- 7
- 10
- 14
xi fi fixi 410........811........129.........1613.........∑fixi= ..........
Find the value of ∑fixi.
- 40
- 88
- 444
- 208
Find the mean for the following data
Class0−1010−2020−3030−4040−50Frequency1098176
Find the mean for the following data.
Class0−2020−4040−6060−8080−100Frequency51112139
Class interval: | 50-70 | 70-90 | 90-110 | 110-130 | 130-150 | 150-170 |
Frequency: | 18 | 12 | 13 | 27 | 8 | 22 |
- 12
- 14
- 16
- 18
If the mean of the given data is 250, then find the value of p.
Class interval Frequency0−1007100−20011200−30015300−400p400−5008 [2 MARKS]
If the mean of the following data is 17, then the value of 'p' is
xi10p182125fi1015799
14
15
24
16
If xi are the mid-points of the class intervals of grouped data, fi are the corresponding frequencies and ¯x is the mean, then ∑fi(xi−¯x) is equal to ____.
2
0
-1
1
∑fx = 5x + 2, ∑f = 12. If the mean of the distribution is 6, what is the value of x?
12
18
15
14
Find the mean for the following data.
Class0−2020−4040−6060−8080−100Frequency51112139