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प्रश्न
The mean of 5 numbers is 27. If one new number is included, the new mean is 25. Find the included number.
उत्तर
Mean of 5 observations = 27
Total sum of 5 observations = 27 × 5 = 135
New mean with 6 numbers
When the new number is included, the mean becomes 25, and the total numbers increase to 6.
On including an observation, the mean of 6 observation = 25 × 6 = 150
⇒ Included observations = Total Mean of 6 observations – Total mean of 5 observations
= 150 − 135 = 15
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संबंधित प्रश्न
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| 60-65 | 10 |
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| 70-75 | 9 |
| 75-80 | 6 |
| 80-85 | 12 |
| 85-90 | 8 |
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