Find the distance between point B and point F. Please help!!!!!!!!!!

I will make you brainlist

vichka [17]

Answer:

i think the aswer is b

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

There are n questions on a multiple choice exam, and for each question, there are four choices. To pass the exam, one must corre

irinina [24]

Answer:

a) 0.352% probability of the student passing

b) 5

c) 1.875

Step-by-step explanation:

For each question, there are only two possible outcomes. Either the student answers it correctly, or he answers it wrong. The probability of correctly answering a question is independent from the probability of correctly answering 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.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

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

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

The expected value of the binomial distribution is:

$E(X) = np$

The variance of the binomial distribution is:

$V(X) = np(1-p)$

For each question, there are four choices.

One choice is correct, so $p = \frac{1}{4} = 0.25$

a. Find the probability of the student passing for n = 10.

0.7*10 = 7

This is $P(X \geq 7)$ when $n = 10$

$P(X \geq 7) = P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10)$

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 7) = C_{10,7}.(0.25)^{7}.(0.75)^{3} = 0.0031$

$P(X = 8) = C_{10,8}.(0.25)^{8}.(0.75)^{2} = 0.0004$

$P(X = 9) = C_{10,9}.(0.25)^{9}.(0.75)^{1} = 0.00002$

$P(X = 10) = C_{10,10}.(0.25)^{10}.(0.75)^{0} \cong 0$

$P(X \geq 7) = P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10) = 0.0031 + 0.0004 + 0.00002 = 0.00352$

0.352% probability of the student passing

b. Find the expected number of questions answered correctly for n = 20.

Here we have n = 20. So

$E(X) = np = 20*0.25 = 5$

c. Find the variance for the number of questions answered correctly for n = 10.

Here we have n = 10.

$V(X) = np(1-p) = 10*0.25*0.75 = 1.875$

5 0

4 years ago

The ratio of mango ice cream to strawberry ice cream is 2 : 5 .Total no. of ice cream is 49.what is the no. of strawberry ice cr

WARRIOR [948]

Answer:

35

Step-by-step explanation:

First, we add the ratio of the mango to strawberry ice cream and we're going to end up with 2+5=7. If we divide 49 by 7, we're going to find out how much we need to multiply to both sides of the ratio to get the specific amounts. So, if we multiply 7 (49/7) to 5, we're going to get 35. Therefore the number of strawberry ice cream is 35.

Also, we can check this by multiplying 7 to 2 as well, where we will end up with 14. 35 + 14 = 49 so we know this is correct!

7 0

3 years ago

The axis of symmetry for the function f(x) = –2x2 + 4x + 1 is the line x = 1. Where is the vertex of the function located?

egoroff_w [7]

Answer:

(1, 3)

Step-by-step explanation:

You are given the h coordinate of the vertex as 1, but in order to find the k coordinate, you have to complete the square on the parabola. The first few steps are as follows. Set the parabola equal to 0 so you can solve for the vertex. Separate the x terms from the constant by moving the constant to the other side of the equals sign. The coefficient HAS to be a +1 (ours is a -2 so we have to factor it out). Let's start there. The first 2 steps result in this polynomial:

$-2x^2+4x=-1$ . Now we factor out the -2:

$-2(x^2-2x)=-1$ . Now we complete the square. This process is to take half the linear term, square it, and add it to both sides. Our linear term is 2x. Half of 2 is 1, and 1 squared is 1. We add 1 into the set of parenthesis. But we actually added into the parenthesis is +1(-2). The -2 out front is a multiplier and we cannot ignore it. Adding in to both sides looks like this:

$-2(x^2-2x+1)=-1-2$ . Simplifying gives us this:

$-2(x^2-2x+1)=-3$

On the left we have created a perfect square binomial which reflects the h coordinate of the vertex. Stating this binomial and moving the -3 over by addition and setting the polynomial equal to y:

$-2(x-1)^2+3=y$