Answer:
3 students got a perfect score.
Step-by-step explanation:
Total number of students in Mrs. Grape's class = 90
Number of students who earned an A = 3/10 of 90
= 
= 27 students
Out of 27 students the number of students who got perfect score
= 
= 3 students
3 students got a perfect score.
Answer:
The probability the man was hit by a Blue Cab taxi is 41%.
Step-by-step explanation:
In terms of bayesian probability, we have to calculate P(B|Wr), or, given the witness saw the right colour, the taxi is from the Blue Cab company.
According to Bayes
P(B|Wr) = P(Wr|B)*P(B)/P(Wr)
P(Wr|B) = 0,8
P(B) = 0.15
To calculate P(Wr), or the probability of the witness of guessing right, we have to consider the two possibilities:
1) The taxi is from Blue Cab (B) and the witness is right (Wr).
2) The taxi is from Green Cab (G) and the witness is wrong (Ww).
The total probality of guessing right is
P(B)*P(Wr) + P(G)*P(Ww) = 0.15*0.8 + 0.85*0.2 = 0.29
So we can calculate:
P(B|Wr) = P(Wr|B)*P(B)/P(Wr) = 0.8*0.15/0.29 = 0.41
The probability the man was hit by a Blue Cab taxi is 41%.
What the other person said
If you do the problem in the order of operations (PEMDAS), it should be B. 18
