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प्रश्न
If the mean of 8 , 14 , 20 , x and 12 is 13, find x.
उत्तर
Numbers are = 8, 14, 20, x, 12
Mean= 13
n = 5
`barx = (x_1 + x_2 + x_3 + .... + x_n)/n`
⇒ `13 = (8+ 14+20+x + 12 )/5`
⇒ `13 = (54+x )/5`
⇒ 54+X=65
⇒ x = 11
The value of x = 11
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संबंधित प्रश्न
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| Age (in years) | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| Frequency | 2 | 4 | 6 | 9 | 8 | 7 | 4 |
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| Weight (kg) | 10 – 15 | 15 – 20 | 20 – 25 | 25 – 30 | 30 – 35 |
| No. of boys | 11 | 25 | 12 | 5 | 2 |
Attempt this question on graph paper.
| Age (yrs ) | 5-15 | 15-25 | 25-35 | 35-45 | 45-55 | 55-65 | 65-75 |
| No.of casualties | 6 | 10 | 15 | 13 | 24 | 8 | 7 |
(1) Construct the 'less than' Cumulative frequency curve for the above data. using 2 cm =10 years on one axis and 2 cm =10 casualties on the other.
(2)From your graph determine :
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(b)the lower quartile
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9, 11, 8, 11, 16, 9, 11, 5, 3, 11, 17 and 8
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| C.I | 0-50 | 50-100 | 100-150 | 150-200 | 200-250 | 250-300 |
| Freq | 4 | 8 | 16 | 13 | 6 | 3 |
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| Variate | 20 | 21 | 22 | 23 | 24 | 25 | 26 |
| Frequency | 21 | 20 | 26 | 35 | 22 | 13 | 10 |
Find the mean of: 12, 9, 6,11 and 17
If the mean of x, x + 2, x + 4, x + 6 and x + 8 is 13, find the value of x. Sum of data.
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