If the mean of the following data is 18.75 , find the value of p.

Explanation

We may perpare the frequency table as given below:
` (##RSA_MATH_IX_C18_SLV_021_S01.png" width="80%">
mean = `(sum(f_(1)xx x_(1)))/(sumf_(1))= (460 +7p)/32`
But, mean = 18.75 (given)
` (460+7p)/32 =18.75 Rightarrow 460 +7p = 18.75 xx 32`
` Rightarrow 460 +7p =600`
` Rightarrow 7p =140 Rightarrow p=20`
Hence p=20