Answer:
C. √2 - 1
Step-by-step explanation:
If we draw a square from the center of the large circle to the center of one of the small circles, we can see that the sides of the square are equal to the radius of the small circle (see attached diagram)
Let r = the radius of the small circle
Using Pythagoras' Theorem 
(where a and b are the legs, and c is the hypotenuse, of a right triangle)
to find the diagonal of the square:



So the diagonal of the square = 
We are told that the radius of the large circle is 1:
⇒ Diagonal of square + r = 1





Using the quadratic formula to calculate r:




As distance is positive,
only
Answer:
7/12.
Step-by-step explanation:
There are 12 numbers totals.
The numbers 1, 7, 11, 8, 2, 4, and 10 are not in Set Q.
There are seven of those numbers which means that the probability of a number not being in Set Q is 7/12.
Answer: 4/5
Step-by-step explanation:
1. split each candy bar into fifths
2. 20 pieces total
3. 20 ÷ 5 = 4
4. So each person gets 4 pieces (4/5)