A because the others are fractions and not a whole number
Answer:
2:1
Step-by-step explanation:
each bird has 2 wings to 1 beak
P(5,2) = n! /(n-r)!
n = 5, r = 2:
= (5 x 4 x 3 x 2 x 1 ) / 3 x 2 x 1
Cancel out common factors:
= 5 x 4 = 20
The answer is 20.