The following table gives the number of pages written by Sarika for completing her own book for 31 days :
 
 Number of pages   \(16-18\) \(19-21\)  \(22-24\)   \(25-27\)  \(28-30\)
 Number of days  2 4 7 8 10
 
Find the mean number of pages .
 
Answer:  
 
The mean is .
 
(Round off to nearest whole number)