Maths by Mr. M. P. Keshari
Example 3. If the mean of the following frequency distribution is 8, find the value of p.
| x | 3 | 5 | 7 | 9 | 11 | 13 |
| f | 6 | 8 | 15 | p | 8 | 4 |
Solution:-
| xi | fi | fi xi |
3 |
6 |
18 |
| 5 | 8 | 40 |
| 7 | 15 | 105 |
| 9 | p | 9p |
| 11 | 8 | 88 |
| 13 | 4 | 52 |
 |
 |
328 + 8p = 303 + 9p
328 - 303 = 9p - 8p
25 = p
| Subjects | Maths (Part-1) by Mr. M. P. Keshari |
| Chapter 9 | Circle |
| Chapter 10 | Tangents to a circle |
| Chapter 11 | Geometrical Construction |
| Chapter 12 | Troigonometry |
| Chapter 13 | Height and Distance |
| Chapter 14 | Mensuration |
| Chapter 15 | Statistics |
| Chapter 16 | Probability |
| Chapter 17 | Co-ordinate Geometry |