Question

answer to three friends each create 4 bags of starter bread dough. after ten days, each of those four bags is then divided into four more bags of dough. how many days pass before 192 bags of dough are created

Answer 1

The answer is 20 days, we can solve this in following way:
Each friend creates 4 bags of dough and after ten days four bags divided into four more bags means:
3 friends x 4 bags = 12 bags  and 12 bags  x 4 = 48 bags
so in next 10 days, the 48 bags will be further divided into 4, so 
48 x 4 = 192 bags
10 days  + next 0 days  = 20 days
so 20 days is the answer.