Answer:
D.) The expected value is 1.78
Step-by-step explanation:
The expected value of a probability distribution is evaluated using the formula.
Expected Value, 
Therefore, from the given probability distribution, we have:
E(X)=(0*0.3)+(1*0.2)+(2*0.16)+(3*0.2)+(4*0.04)+(5*0.1)
E(X)=1.78
The Expected value of X is 1.78.
The correct option is D.
B. 9 I think because it looks like it is bisected in the middle to cut into two equal parts. Please correct me if I am wrong. Thanks.
Let q be the number of 25 cent coins.
Let d be the number of 10 cent coins.
0.25q+0.10d= 3.95...(1)
q-d=6...(2)
(2)-> q-d= 6
q-d+d= 6+d
q= 6+d...(2a)
(2a)-> (1) 0.25q+0.10d=3.95
0.25(6+d)=0.10d= 3.95
1.95+0.25d+0.10d= 3.95
0.35d= 3.95-1.5
0.35d/0.35= 2.45/0.35
d= 7...(3)
(3)->(2) q-d= 6
q-7= 6
q=6+7
q= 13
There are 13 quarters and 7 dimes.
C 12 minutes is the correct answer. Hope this helps :)