Answer:
D
Step-by-step explanation:
I can’t give a step-by-step explanation but it’s D
Answer:
C 40
Step-by-step explanation:
1 blue : 2 white
multiply both sides of the proportion by 20 to reach 20 blue marbles
20 blue: 40 white
Answer:

Step-by-step explanation:
First of all, the number before the decimal would be the whole number of the fraction.
So, 
Then, you would put 0.83 over a fraction.
So because you cannot simplify it anymore, it would be 