Answer:
The probability is 0.9211
Step-by-step explanation:
Let's call K the event that the student know the answer, G the event that the student guess the answer and C the event that the answer is correct.
So, the probability P(K/C) that a student knows the answer to a question, given that she answered it correctly is:
P(K/C)=P(K∩C)/P(C)
Where P(C) = P(K∩C) + P(G∩C)
Then, the probability P(K∩C) that the student know the answer and it is correct is:
P(K∩C) = 0.7
On the other hand, the probability P(G∩C) that the student guess the answer and it is correct is:
P(G∩C) = 0.3*0.2 = 0.06
Because, 0.3 is the probability that the student guess the answer and 0.2 is the probability that the answer is correct given that the student guess the answer.
Therefore, The probability P(C) that the answer is correct is:
P(C) = 0.7 + 0.06 = 0.76
Finally, P(K/C) is:
P(K/C) = 0.7/0.76 = 0.9211
C. chicken, spinach
(1 entree and 1 vegetable)
Answer:
4
Step-by-step explanation:
Answer:
-5n + 8
Step-by-step explanation:
<u>1. What is the difference?</u>
The sequence goes down by 5. This means that the formula will have -5n in it.
<u>2. Work out the term before the first term.</u>
The first term is 3, and we know that the sequence goes up by 5. So, to get the term before 3 we would add 5.
3 + 5 = 8 Remember, this is positive 8. (+8)
<u>3. Put that term at the end of the equation. </u>
We have -5n already and we just worked out the term before the first one which is positive 8 - so put that at the end of the equation.
-5n + 8 This is our answer!
Just to prove it works:
<em>Substitute: n = term</em>
Lets see if we can get the 3rd term which is -7. (n = 3)
-5(3) + 8
-15 + 8 = -7
See, it works!