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
Answer:
O= 90 because it is a right angle, 360 degrees (which is the whole circle) minus (50+90), equals 220.
Answer: x^2+2x+1
Step-by-step explanation:
Answer:
Alright, the answer to the equation -52+3= -49
Step-by-step explanation:
I don't know how the heck Marcus and Jeremy got -22 and 28 but both are wrong. If there were a picture so I could see their work, I would be able to figure it out.
Anyways, The math is:
-52 + 3 which is pretty much 52-3 and then the answer has a negative sign.
-52 goes up 3 because technically the negative sign is down. Counting up 3 from 52 equals -49.
