Respuesta :

Answer:

18 is .20

19 is c+5 over 3

Step-by-step explanation:

18.

p= 4C 1 /4C1 * 5C1 = 4 / 4*5 = .20

19.

(3a - 5) / c = 1

3a - 5 = c

3a = c + 5

a = (c + 5) / 3
#18 is B because 4/20 possibilities add up to ten.
#19 is C because the bs cancel out and you get 3a-5=c -> 3a=c+5 -> a= (c+5)/3