Answer:
A. 1:8
Step-by-step explanation:
We have been given that several students were asked to name the kinds of animals they saw in the past week at the park.
Dogs: 8
Cat: 2
Fish: 4
Lizard: 2
We are asked to find the ratio that compares the number of cats seen to the total number of animals seen.
Let us find total number of animal by adding each type of animals as:


We can see that the students saw 2 cats, so ratio of cats to total animals would be
.
Dividing 2 and 16 by 2, we will get:

Therefore, the ratio 1:8 compares the number of cats seen to the total number of animals seen and option A is the correct choice.
Answer:
Let X be the number of times the target is hit. The probability P(X≥1) then equals 1 minus the probability of missing the target three times:
P(X≥1) = 1− (1−P(A)) (1−P(B)) (1−P(C))
= 1−0.4*0.3*0.2
= 0.976
To find the probability P(X≥2) of hitting the target at least twice, you can consider two cases: either two people hit the target and one does not, or all people hit the target. We find:
P(X≥2)=(0.4*0.7*0.8)+(0.6*0.3*0.8)+(0.6*0.7*0.2)+(0.6*0.7*0.8) = 0.788
Step-by-step explanation: