0.8 has one decimal.. so... let's make it a fraction first, by using one zero with a one as denominator.

is between any of those, among many other fractions as well.
Simple....
you have:

You're trying to find b..so isolate it...

leaving you
a=c*b
still not done....


Thus, your answer.
Answer:
20
Step-by-step explanation:
set up equation
13/x=65/100
cross multiple: 1300=65x
divide 1300/65=20
Answer:
12
Step-by-step explanation:
Answer: B. Every 10th students that enters the cafeteria
Explanation:
B is a random sample, while A, C, and D are biased.