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प्रश्न
If class mark is 10 and class width is 6 then find the class.
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उत्तर
Let x be the upper class limit and y the lower class limit.
class mark = 10 ..[given]
class mark = `(x + y)/2`
10 = `(x + y)/2`
x + y = 20 ...(i)
class width = 6 ...[given]
x - y = 6 ....(ii)
Adding equation (i) and (ii)
x + y = 20
+ x - y = 6
2x = 26
x = `26/2`
x = 13
Putting the value x = 13 in equation (i),
x + y = 20
13 + y = 20
y = 20 -13
y = 7
∴ the class is 7-13.
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संबंधित प्रश्न
For class interval 20-25 write the lower class limit and the upper class limit.
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| 12 - 13 | `cancel(bb|bb|bb|bb|)` | `square` |
| 13 - 14 | `cancel(bb|bb|bb|bb|)` `cancel(bb|bb|bb|bb|)` `bb|bb|bb|bb|` | `square` |
| 14 - 15 | `square` | |
| 15 - 16 | `bb|bb|bb|bb|` | `square` |
| `bb(N = sumf = 35)` |
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| 25 - 34 | ...... | 15 |
| 35 - 44 | ...... | 28 |
| 45 - 54 | 21 | ...... |
| 55 - 64 | 16 | ...... |
| 65 - 74 | ...... | 73 |
| 75 - 84 | 12 | ...... |
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| Below 4 | 0 |
| Below 7 | 85 |
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| Below 16 | 300 |
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| Marks | No. of students |
| less than 10 | 6 |
| less than 20 | 15 |
| less than 30 | 30 |
| less than 40 | 39 |
| less than 50 | 53 |
| less than 60 | 70 |
Given below are the marks obtained by 30 students in an examination:
|
08 |
17 |
33 |
41 |
47 |
23 |
20 |
34 |
|
09 |
18 |
42 |
14 |
30 |
19 |
29 |
11 |
|
36 |
48 |
40 |
24 |
22 |
02 |
16 |
21 |
|
15 |
32 |
47 |
44 |
33 |
01 |
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| C.I | C.F |
| 5 - 10 | 18 |
| 10 - 15 | 30 |
| 15 - 20 | 46 |
| 20 - 25 | 73 |
| 25 - 30 | 90 |
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| Frequency | 6 | 12 | 10 | 15 | 9 | 2 |
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d. The upper and lower limits of the sixth class.
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