Answer :

To find the mean (denoted as [tex]\(\bar{X}\)[/tex]) in a continuous series given [tex]\(\Sigma f = 20p + 7\)[/tex] and [tex]\(\Sigma fm = 100p + 35\)[/tex], we follow these steps:

1. Write down the formulas provided:
- Total frequency: [tex]\(\Sigma f = 20p + 7\)[/tex]
- Sum of all midpoints (frequency times midpoint): [tex]\(\Sigma fm = 100p + 35\)[/tex]

2. Recall the formula for the mean in a continuous series:
- [tex]\(\bar{X} = \frac{\Sigma fm}{\Sigma f}\)[/tex]

3. Substitute [tex]\(\Sigma f\)[/tex] and [tex]\(\Sigma fm\)[/tex] into the formula for the mean:
[tex]\[\bar{X} = \frac{100p + 35}{20p + 7}\][/tex]

4. Simplify the expression (if possible):
- There is no common factor for [tex]\(100p+35\)[/tex] and [tex]\(20p+7\)[/tex], so the expression remains as is.

Thus, the mean [tex]\(\bar{X}\)[/tex] is:
[tex]\[ \bar{X} = \frac{100p + 35}{20p + 7} \][/tex]

So, in conclusion, the mean of the continuous series is:
[tex]\[ \boxed{\frac{100p + 35}{20p + 7}} \][/tex]