Answer:
0.0111% probability that he answers at least 10 questions correctly
Step-by-step explanation:
For each question, there are only two outcomes. Either it is answered correctly, or it is not. The probability of a question being answered correctly is independent from 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.
A multiple-choice examination has 15 questions, each with five answers, only one of which is correct.
This means that 
What is the probability that he answers at least 10 questions correctly?









0.0111% probability that he answers at least 10 questions correctly
69,017,409 is the correct answer
Answer:

Step-by-step explanation:
Since, By the given diagram,
The side of the inner square = Distance between the points (0,b) and (a-b,0)


Thus the area of the inner square = (side)²


Now, the side of the outer square = Distance between the points (0,0) and (a,0),


Thus, the area of the outer square = (side)²

Hence, the ratio of the area of the inner square to the area of the outer square

Answer:
The rental rate for the Fords is of $12 per day.
Step-by-step explanation:
This question is solved using a system of equations.
I am going to say that:
x is the cost of a Nissan.
y is the cost of a Ford.
z is the cost of a Chevrolet.
Three Nissans, two Fords, and four Chevrolets can be rented for $106 per day.
This means that:

Two Nissans, four Fords, and three Chevrolets cost $107 per day
This means that:

Four Nissans, three Fords, and two Chevrolets cost $102 per day.
This means that:

From the first equation:



Replacing into the third equation:


From the second equation:









Find the rental rate for the Fords.
We have to find y, so:






The rental rate for the Fords is of $12 per day.