Question
Find the mean of the following data using direct method :
| Class-interval | 0 - 4 | 5 - 9 | 10 - 14 | 15 - 19 |
| Frequency | 2 | 8 | 7 | 3 |
✓
Answer
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→(i) find the value of $p$.
(ii) with this value of $p$, factorise the above expression completely
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