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
14:

56/8 = 7 so multiply 1/2 by 7/1 to get the unidentified fraction "x/y"
1/2 · 7/1 = 7/2 or 3 1/2
15. 
to get from 100 to 5, you would divide by 20, so to solve for x, multiply 2 by 20, to get a product of 40.
40/100 = 40% or D
16.
A
Two functions have equal values where their graphs cross.
A) The solution to the pair of equations
.. y = p(x)
.. y = f(x)
will be where the graphs intersect, at (x, y) = (-3, -3).
B) We already know that (-3, -3) is one solution to y=f(x). The graph also appears to go through the point (0, 0).
C) p(x) = g(x) where their graphs cross, at x = -6. Both functions have the value 1 for that value of x.
Answer:
i'm not too good in this, but i believe the answer is -3
Step-by-step explanation:
the hcf, highest common factor, of both -3 and -15 is -3, hence making the answer -3? if this is incorrect, i apologize.