Help please its a grade!

The diagram shows a sector of a circle radius 10 cm. the angle is 135 degrees

Black_prince [1.1K]

Answer:

The perimeter is 43.6 cm

Step-by-step explanation:

In this question, we are tasked with calculating the perimeter of the sector.

Firstly, we define what a sector is. A sector is part of a circle which is is blinded by two radii and an arc. Hence we say a sector contains two radii.

Thus, to calculate the perimeter of the sector, we need the length of the arc added to 2 * length of the radius

Let’s calculate the length of the arc.

Mathematically, this is theta/360 * 2 * pi * r

where theta is the angle subtended at the middle of the circle which is 135 according to the question, and our radius is 10cm

Thus, we have

135/360 * 2 * 22/7 * 10 = 23.57 cm

Adding two radii to this, we have;

23.57 + 2(10)

= 23.57 + 20 = 43.57 = 43.6 cm to 1 decimal place

5 0

3 years ago

A bag contains 4 blue marbles and 2 yellow marbles. Two marbles are randomly chosen (the first marble is NOT replaced before dra

VMariaS [17]

Answer:

0.4 = 40% probability that both marbles are blue.

0.0667 = 6.67% probability that both marbles are yellow.

53.33% probability of one blue and then one yellow

If you are told that both selected marbles are the same color, 0.8571 = 85.71% probability that both are blue

Step-by-step explanation:

To solve this question, we need to understand conditional probability(for the final question) and the hypergeometric distribution(for the first three, because the balls are chosen without being replaced).

Hypergeometric distribution:

The probability of x sucesses is given by the following formula:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

In which:

x is the number of sucesses.

N is the size of the population.

n is the size of the sample.

k is the total number of desired outcomes.

Combinations formula:

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

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

Conditional Probability

We use the conditional probability formula to solve this question. It is

$P(B|A) = \frac{P(A \cap B)}{P(A)}$

In which

P(B|A) is the probability of event B happening, given that A happened.

$P(A \cap B)$ is the probability of both A and B happening.

P(A) is the probability of A happening.

What is the probability that both marbles are blue?

4 + 2 = 6 total marbles, which means that $N = 6$

4 blue, which means that $k = 4$

Sample of 2, which means that $n = 2$

This is P(X = 2). So

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

$P(X = 2) = h(2,6,2,4) = \frac{C_{4,2}*C_{2,0}}{C_{6,2}} = 0.4$

0.4 = 40% probability that both marbles are blue

What is the probability that both marbles are yellow?

4 + 2 = 6 total marbles, which means that $N = 6$

2 yellow, which means that $k = 2$

Sample of 2, which means that $n = 2$

This is P(X = 2). So

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

$P(X = 2) = h(2,6,2,2) = \frac{C_{2,2}*C_{4,0}}{C_{6,2}} = 0.0667$

0.0667 = 6.67% probability that both marbles are yellow.

What is the probability of one blue and then one yellow?

Total is 100%.

Can be:

Both blue(40%)

Both yellow(6.67%)

One blue and one yellow(x%). So

40 + 6.67 + x = 100

x = 100 - 46.67

x = 53.33

53.33% probability of one blue and then one yellow.

If you are told that both selected marbles are the same color, what is the probability that both are blue?

Conditional probability.

Event A: Both same color

Event B: Both blue

Probability of both being same color:

Both blue(40%)

Both yellow(6.67%)

This means that $P(A) = 0.4 + 0.0667 = 0.4667$

Probability of both being the same color and blue:

40% probability that both are blue, which means that $P(A \cap B) = 0.4$

Desired probability:

$P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.4}{0.4667} = 0.8571$

If you are told that both selected marbles are the same color, 0.8571 = 85.71% probability that both are blue

8 0

3 years ago

Find an irrational number that is between 5.2 and 5.5

uysha [10]

Answer:

answer is 5.3 cuz I am smart I learned this so I'm here to help

6 0

3 years ago

Read 2 more answers

PLEASE HELP!!!!! !!!!!!!!!!!!

valina [46]

Answer:

31.9secs

6,183.3m

Step-by-step explanation:

Given the equation that models the height expressed as;

h(t ) = -4.9t²+313t+269

At the the max g=height, the velocity is zero

dh/dt = 0

dh/dt = -9,8t+313

0 = -9.8t + 313

9.8t = 313

t = 313/9.8

t = 31.94secs

Hence it takes the rocket 31.9secs to reach the max height

Get the max height

Recall that h(t ) = -4.9t²+313t+269

h(31.9) = -4.9(31.9)²+313(31.9)+269

h(31.9) = -4,070.44+9,984.7+269

h(31.9) = 6,183.3m

Hence the maximum height reached is 6,183.3m

3 0

3 years ago

An Xbox has a retail price of $350. Best Buy is offering a 15% discount on the system. How much will the Xbox cost after the dis

arlik [135]

Answer:

About 297.50$

becuase since i actually have an xbox with that same discount i know the answer

7 0

3 years ago

Read 2 more answers