can someone help me on this one?

Answer:
A=15
B=13??
C=15
D=85
Step-by-step explanation:
B is the only one I'm not sure
Answer:
A. 3/x = 20/100
x=15
B. 3/23 = x/100
300=23x
x=13
C. 3/20 = x/100
x=15
D. 17/x=20/100
x=85
Let me know if you have any other questions