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
12.5663706144 or yes, 12.57
The distance between the trains is changing at the rate of (70 -60) = 10 mph. They will be in the same place (45 mi)/(10 mi/h) = 4.5 hours after they leave their respective cities. They will be 10 miles apart both 1 hour before that time and one hour after that time.
The trains will be 10 miles apart 3.5 hours after leaving.
They will be 10 miles apart the second time 5.5 hours after leaving.
Answer:
6 liters
Step-by-step explanation:
Given:
Renata's recipe for her famous Kale 'n' Clam Quencher calls for kale juice and clam juice in a 3:1 ratio.
If Renata pours 18 liters of fresh kale juice, how many liters of clam juice should she add to maintain this ratio?
Solution:
Ratio to be maintain by using kale juice and clam juice = 3 : 1 ( given)
Renata pours fresh kale juice = 18 liters
We have to calculate quantity of clam juice should be added to maintain this ratio:-
Let quantity of clam juice should be added = 
<u>Ratio to be maintain : : quantity of kale juice : quantity of clam juice</u>

By cross multiplication:

By dividing both sides by 3

Thus, 6 liters of clam juice should she add.