you plant 30 african violet seeds and 9 of them sprout use experimental probability to predict how many will sprout if you plant 20 seeds

Given that out of 30 planted seeds only 9 of the m sprouted, then:
Experimental probability =(number of occurrence of event)/(total number of trials made)
=9/30
=3/10
thus the number of seeds that will sprout given that 20 seeds we planted will be:
3/10×20
=6 seeds