19. The average score of a cricketer in 2 matches is 27 and that in 3 others is 32. Then his average score in 5 matches is :

20. The average weight of 19 students is 15 kg. By the admission of a new student the average weight is reduced to 14.8 kg. The weight of the new student is :

21. The average of 13 results is 68. The average of first seven is 63 and that of the last seven is 70, the seventh result is :