Answer:
1/20 is 5%
Step-by-step explanation:
1/20 = 5%
20/20 = 100%
100 ÷ 20 = 5%
1/20 x 100 = 0.05 x 100 = 5%
Answer:
0.0082 = 0.82% probability that he will pass
Step-by-step explanation:
For each question, there are only two possible outcomes. Either the students guesses the correct answer, or he guesses the wrong answer. The probability of guessing the correct answer for a question is independent of other questions. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
In this problem we have that:
.
If the student makes knowledgeable guesses, what is the probability that he will pass?
He needs to guess at least 9 answers correctly. So









0.0082 = 0.82% probability that he will pass
Answer:
y = 12
Step-by-step explanation:
Use the equation y = kx
Plug in x and y to find k:
2 = k(16)
1/8 = k
Then, plug in 1/8 as k and 96 as x to find y:
y = 1/8(96)
y = 12
Answer:
x = 4 , y = -1
Step-by-step explanation:
x - 3y = 7 -- (1)
3x - 3y = 15 -- (2)
Rewriting (1), x = 3y + 7 -- (1)'
Substituting (1)' into (2),
3 ( 3y + 7 ) - 3y = 15
9y + 21 - 3y = 15
6y = -6
y = -1 -- (3)
Substituting (3) into (1),
x - 3 ( - 1 ) = 7
x + 3 = 7
x = 4 -- (4)
According to (3) and (4),
x = 4 , y = -1