B 1/4
Explanation: The total number of pizza you need for everyone is 4. Each person gets 1 out of the 4 pieces aka 1/4
1) 10.0 + 5.0 + .8
2) 1.000 + 0.050 + 0.008
3) 0.000 + 0.100 + 0.050 + 0.008
It would be 89.
You can also just look up a list of prime numbers online.
That is an ratio, what are you asking for??