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3 years ago

Hurryyyyyy!!! which expression is equivalent to 7(1+3)? a.1+21b.7+21c 7+3d.7+4

Mathematics

1 answer:

n200080 [17]3 years ago

4 0

Answer:

b. 7+21

Step-by-step explanation:

If you do 1+3=4 and then 4 times 7 that equals 28. When you do 7+21 that equals 28 too. So b is the answer

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PLZ PLEASE OMG PLEASE

STatiana [176]

Answer:

N=N so b

Step-by-step explanation:

Because in LN=NP the reflexive property essentially takes this info and repeats itself N=N

6 0

3 years ago

53% of U.S. adults have very little confidence in newspapers. You randomly select 10 U.S. adults. Find the probability that the

faltersainse [42]

Answer:

$P(X = 5) = 0.2423$

$P( X \ge 6 )= 0.4516$

$P( X < 4 )= 0.12694$

Step-by-step explanation:

From the question we are told that

The population proportion is p = 0.53

The sample size is n = 10

Generally the distribution of the confidence of US adults in newspapers follows a binomial distribution

i.e

$X \~ \ \ \ B(n , p)$

and the probability distribution function for binomial distribution is

$P(X = x) = ^{n}C_x * p^x * (1- p)^{n-x}$

Here C stands for combination hence we are going to be making use of the combination function in our calculators

Generally the probability that the number of U.S. adults who have very little confidence in newspapers is exactly five is mathematically represented as

$P(X = 5) = ^{10}C_5 * 0.53^5 * (1- 0.53)^{10-5}$

=> $P(X = 5) = 252 * 0.04182 * 0.023$

=> $P(X = 5) = 0.2423$

Generally the probability that the number of U.S. adults who have very little confidence in newspapers is at least six is mathematically represented as

$P( X \ge 6 )= P( X = 6) + P( X = 7) + P( X = 8) + P( X = 9) + P( X = 10)$

=> $P( X \ge 6 )= [^{10}C_6 * [0.53]^6 * (1- 0.53)^{10-6}] + [^{10}C_7 * [0.53]^7 * (1- 0.53)^{10-7}] + [^{10}C_8 * [0.53]^8 * (1- 0.53)^{10-8}] + [^{10}C_9 * [0.53]^9 * (1- 0.53)^{10-9}] + [^{10}C_{10} * [0.53]^{10} * (1- 0.53)^{10-10}]$

=> $P( X \ge 6 )= [0.227] + [0.1464] + [0.0619] + [0.0155] + [0.00082]$

=> $P( X \ge 6 )= 0.4516$

Generally the probability that the number of U.S. adults who have very little confidence in newspapers is less than four is mathematically represented as

$P( X < 4 )= P( X = 3) + P( X = 2) + P( X = 1) + P( X = 0)$

=> $P( X < 4 )= [^{10}C_3 * 0.53^3 * (1- 0.53)^{10-3}] + [^{10}C_2 * 0.53^2 * (1- 0.53)^{10-2}] + [^{10}C_1 * 0.53^1 * (1- 0.53)^{10-1}] + [^{10}C_0 * 0.53^0 * (1- 0.53)^{10-0}]$

=> $P( X < 4 )= 0.09051 + 0.03 + 0.0059 + 0.000526$

=> $P( X < 4 )= 0.12694$

5 0

3 years ago

X+x-z; use x=3 & z=4

nadezda [96]

Answer:

Step-by-step explanation:

Order of operations is not as applicable in this situation because we're just dealing with addition and subtraction. This is a simple case of plugging in values for the given expression.

x = 3

z = 4

So it becomes...

3 + 3 - 4

6 - 4

So with the given expression of x + x - z and the given values of x = 3 and z = 4, the expression should sum to: 2

6 0

3 years ago

A student knows the height of a pyramid and the area of its base. What should the student do to find the volume of the pyramid

Varvara68 [4.7K]

Answer:

Multiply the area of the base by the height and divide by 3.

Step-by-step explanation:

V = (1/3)Bh

where B = area of the base, and

h = height

Answer: Multiply the area of the base by the height and divide by 3.

5 0

3 years ago

Read 2 more answers

A new restaurant is attracting customers with searchlights has a radius of 2 feet. What is the searchlights circumference?

Assoli18 [71]

Answer:

12.56 feet

Step-by-step explanation:

The perimeter of a shape is the sum of all its side.

Since circle doesn't have "sides", the perimeter is the length of the whole circle. This has the name "circumference".

The circumference of a circle has the formula:

$C=2\pi r$

Where

C is the circumference (perimeter of a circle)

r is the radius

Given,

r = 2 feet

We substitute and find the circumference, using 3.14 as $\pi$ ,

$C=2\pi r\\C=2(3.14) (2)\\C=12.56$

Hence, the circumference is 12.56 feet

5 0

3 years ago