Answer: a) Explicit formula :
b) Recursive formula :
and 
Step-by-step explanation:
Since we have given that
Number of grams of yeast in a culture dish initially = 9 grams
According to question, a certain culture of year increases by 50 % every three hours.
So, the explicit formula will be

And the recursive formula will be

Hence, a) Explicit formula : 
b) Recursive formula :
and 
A decrease in the ratio 4:5 implies that :
New quantity:Old quantity = 4:5
Let the new quantity be 





So, the new quantity is 32
Answer:
Step-by-step explanation:
1. 24
2. 315.6
3. 370
hopefully this helps and sorry if i did it wrong god bless love
Answer:
9000
Step-by-step explanation:
20 x 18 x 25
20 options for one member
18 options for another member
25 members for the last member