This question is incomplete because it was not written properly
Complete Question
A teacher gave his class two quizzes. 80% of the class passed the first quiz, but only 60% of the class passed both quizzes. What percent of those who passed the first one passed the second quiz? (2 points)
a) 20%
b) 40%
c) 60%
d) 75%
Answer:
d) 75%
Step-by-step explanation:
We would be solving this question using conditional probability.
Let us represent the percentage of those who passed the first quiz as A = 80%
and
Those who passed the first quiz as B = unknown
Those who passed the first and second quiz as A and B = 60%
The formula for conditional probability is given as
P(B|A) = P(A and B) / P(A)
Where,
P(B|A) = the percent of those who passed the first one passed the second
Hence,
P(B|A) = 60/80
= 0.75
In percent form, 0.75 × 100 = 75%
Therefore, from the calculations above, 75% of those who passed the first quiz to also passed the second quiz.
6x+7y=32 and 2x+5y=16
if you add the two equations you get the first answer and if you subtract the two equations you get the second answer
This is a basic addition/subtraction question. It's saying that they started at the 50 yard line. On the play, they gained 7 yards. So, we'll add 50+7 = 57.
They're at the 57 yard line at this point. On the second play they lost 10 yards (how unfortunate). Thereby, we will subtract 57-10=47.
50 yards +7 yards. -10 yards.
The answer will be that they'll be on the 47 yard line on the next play.
You round down so 2.3 goes to 2