which answer is right and please explain

Answer:

All except the 3rd one

the one with 20 and 25

Using the Empirical Rule, it is found that her finishing time will be between 70 and 82 seconds in 95% of her races.

It states that, for a normally distributed random variable:

In this problem, the mean is of 76 seconds and the standard deviation is of 3 seconds, then:

76 - 2 x 3 = 70.

76 + 2 x 3 = 82.

Which means that values between 70 and 82 seconds are within 2 standard deviations of the mean, hence the percentage is of 95%.

More can be learned about the Empirical Rule at https://brainly.com/question/24537145

Using the depreciation formula:

start value x percent of value^time

850 x 0.75^3 = $358.59

answer: $358.59

Answer: $358.59

Step-by-step explanation:

[tex]$$After one year the laptop computer's price is:$$\begin{aligned}&=\$ 850-\$ 850 \times 25 \% \\&=\$ 850-\$ 212.5 \\&=\$ 637.5\end{aligned}$$[/tex]

[tex]$$ Again two year the computer's price is:$$\begin{aligned}&=637.5-25 \% \text { of } 637.5 \\&=637.5-159.375 \\&=\$ 478.125\end{aligned}$$[/tex]

[tex]\bold{\text { So a fair price for the computer is } \$ 358.59}[/tex]

[tex]\begin{aligned}\\\bold{Or}\text { Simply Calculate as } &=(\text { Purchase price }) \times(1-25 \%)^\text{time} \\&=850 \times(1-0.25)^{3} \\&=850 \times(0.75)^{3} \\\bold{&=\$358.59}\end{aligned}[/tex]

The number of the correct spellings is 28.

The Percentage is defined as representing any number with respect to the 100. It is denoted by the sign %.

Given that:-

The number of the spellings are:-

N = 40 x 70% = 28

N = 40 x  (70/100)  =  28

Therefore the number of the correct spellings is 28.

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#SPJ2

Answer:

Option C, the second one. (B and C are switched)

Step-by-step explanation:

a * a = a2

a * b = +ab

⬇️

2ab

⬆️

b * a = +ba or +ab

Two b's make b2 and don't worry, even with the negative sign it is a b2.

Answer:

positive interger.....

Answer:

m + 7

Step-by-step explanation:

→ Collect like terms

3.8m - 2.8m + 7

→ Simplify

m + 7

Answer:

20 and 10

These are the only two possible numbers who match those descriptions.

Answer:

3:10

Step-by-step explanation:

3:10 is the ratio form of 3/10

The value of a, b and <A are 17.4, 119.3 and 42 degrees respectively

From the given right angles triangle, we have the following parameters;

<A + 48 + 90 = 180 (sum of angles in a triangle)

<A =180 - 138

<A = 42 degrees

Using the SOH CAH TOA identity

sin48 = b/26

b = 26sin48

b = 19.3

For the value of a

sin42 = a/26

a = 26sin42

a = 19.3

a =17.4

Hence the value of a, b and <A are 17.4, 119.3 and 42 degrees respectively

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Answer:

Step-by-step explanation:

There is no difference between the two fractions. I can show you this in the following way, assuming you understand the distributive property. We can write the fraction -7/2 in the following way:

[tex]-\frac{7}{2} =-1(7*2^-^1)[/tex]

Hopefully you agree with me that we can bring the 2 into the numerator if we switch the signs of the exponent. And hopefully you agree that a negative sign is equivalent to multiplying by -1. Therefore, this negative 1 can distribute to the 7 or the 2. It really does not matter. To sum this up:

[tex]-\frac{7}{2} =\frac{-7}{2} =\frac{7}{-2}[/tex]

Answer:

20,000×17 gives 340,000

340,000×68 which gives 23,120,000

Answer:

[tex]\mathrm{1 \dfrac{ 1 }{ 6 }\:cups}[/tex]

Step-by-step explanation:

Given from the graph:

There is  [tex]\frac{1}{2}[/tex] cups of paint for one jar

There are 3 cups of paint for three jars

There is 1 [tex]\frac{1}{2}[/tex] cups of paint for one jar

There is 2 cups of paint for one jar

total amount of jars = 6

But since we need to find the amount of cups in each jar, we do:

[tex]\dfrac{ 1 }{ 2 } +3+1 \dfrac{ 1 }{ 2 } +2[/tex]

Add [tex]\frac{1}{2}[/tex] and 1 [tex]\frac{1}{2}[/tex]

[tex]2+3+2[/tex]

Add 2 and 3

[tex]5+2[/tex]

Add 5 and 2

[tex]7[/tex]

total cups of paint = 7

Then we need to find how much paint could be splitted equally among the 6 jars, so we do the following:

total amount of jars = 6

total cups of paint = 7

We divide the total amount of jars by the total cups of paint

7 ÷ 6

Divide 7 by 6

[tex]\dfrac{ 7 }{ 6 }[/tex]

[tex]= 1 \dfrac{ 1 }{ 6 }[/tex]

[tex]\mathrm{Answer: 1 \dfrac{ 1 }{ 6 }\:cups}[/tex]

2 1/2 pounds = 2.5 pounds

A pound of apples cost $1.30 -> 2.5 pounds of apples cost 1.3 x 2.5 = 3.25

-> Answer : B

Answer:

The Turks burned down Constantinople

Answer:

97 oz

Step-by-step explanation:

12 oz per pound

8 pounds + 1 oz

(12 · 8)+ 1

97 oz

Hope this helps!

Answer:

I think the answer is 15 but I am not sure hoping this helps good luck

Answer:

its 13

Step-by-step explanation:

Answer:

Below in bold.

Step-by-step explanation:

1) as ABCD is a rhombuc AC bisects < BAD and < BCD .

Therefore < CAD = 1/2 * 104 = 52 degrees.

2) < ACG  = < ADC +  < CAD  ( External angle of triangle theorem)

Therfore  < ACG = 76 + 52 = 128 degrees.

Answer:

the x is 538

Step-by-step explanation:

sorry if im not right

Answer:

33 cm²

Step-by-step explanation:

Formula

Solving

Answer:

33 cm²

Step-by-step explanation:

Since the pyramid has a square base, the area of each of the triangular sides will be the same.

Therefore, to calculate the total surface area, find the area of one triangle, multiply it by 4, then add it to the area of the square base.

Formulae

Area of a square = x³  (where x is the side length)

Area of a triangle = 1/2 × base × height

Calculation

area of the square base = 3² = 3 × 3 = 9 cm²

area of one triangle = 1/2 × 3 × 4 = 6 cm²

Solution

Total area = area of the square base + 4 × area of one triangle

                 = 9 + (4 × 6)

                 = 9 + 24

                 = 33 cm²

Answer:

443.14

Step-by-step explanation:

A=6ah+33a2

=6·4·15+3·3·42

≈443.13844

Answer:

I believe the answer is 88 if correct please consider brainliest

<3

Step-by-step explanation:

Answer:

it is c

Step-by-step explanation:

:)

The sine equation is  [tex]\rm y = 10sin(\frac{\pi}{15} t)+35[/tex]  an option (c) is correct.

It is given that the blades of a windmill turn on an axis that is 35 feet above the ground. the blades are 10 feet long and complete two rotations every minute.

It is required to model the sine equation.

Trigonometry is a branch of mathematics that deals with the relationship between sides and angles of a right-angle triangle.

We know the standard equation for the sine equation:

[tex]\rm y = Asin(wx)+h[/tex]

Where [tex]\rm T=\frac{2\pi}{w}[/tex]

[tex]\rm w = \frac{2\pi}{30}[/tex]   ( In one minute, they complete two rotations.)

[tex]\rm w = \frac{\pi}{15}[/tex]  ( T = 30)

At time t=0, the blade is horizontal. Hence, at t = 0, h = 35

And A = 10

Put all the values in the sine equation:

[tex]\rm y = 10sin(\frac{\pi}{15} t)+35[/tex]

Thus, the sine equation is  [tex]\rm y = 10sin(\frac{\pi}{15} t)+35[/tex] an option (c) is correct.

Know more about trigonometry here:

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Answer:

100 DEGREES

Step-by-step explanation:

Supplementary means they add to 180 degrees

4x + 5x = 180

x = 20

smaller angle  4 (20) = 80

 learger angle 5 (200 = 100

Answer:

50/50

Step-by-step explanation:

Answer:

depends on how many there are in a deck. But going from the usual, it would be 2/52

Step-by-step explanation:

(52 is how many cards there are, if theres a different amount then change it to that)

Answer:

$185.94

Step-by-step explanation:

5,867+2,510= 8,377

8,377÷50c= 167.54

167.54+18.40= $185.94

A:

5=2+3

-> right triangle

B:

5=4+3

-> not a right triangle

C.

36= 25+16

36= 41

-> not a right triangle

D.

49= 25+25

49=50

-> not a right triangle

E.

100= 36+ 64

100= 100

-> right triangle

Answer:

Step-by-step explanation:

The median is the middle number (or average of middle two numbers if data set has even number of elements) of the data set.

According to the graph, the data set has 9 elements.

The 5th number in the set is the median, which is 14

14

Step-1: Prepare a table that represents the number of dots above a specific number:

[tex]\text{Dots above 10}: || \\ \text{Dots above 12}: | \\ \text{Dots above 13}: | \\ \text{Dots above 14}: | \\ \text{Dots above 15}: | \\ \text{Dots above 18}: | \\ \text{Dots above 19}: ||[/tex]

Step-2: Put the values in ascending or descending upon your choice:

[tex]10, 10, 12, 13, 14, 15, 18, 19, 19[/tex]

Step-3: Determine wether the total number of digits in the data is even or odd. This will help us find the median.

[tex]\text{9 digits in total}\\\\\text{The number of digits is \underline{odd}}[/tex]

Since the number of digits is odd, we will use the formula (a + 1)/2

(where a is the number of digits in the data)

Step-4: Substitute the number of digits in the formula.

⇒ (a + 1)/2th

⇒ (9 + 1)/2th

⇒ (10)/2th

⇒ 5th digit is median

Step-5: Look for the 5th digit in the data. That digit is your median.

[tex]10, 10, 12, 13, \underline{\underline{14}}, 15, 18, 19, 19[/tex]

The median of the dot plot is 14.

Answer:

Step-by-step explanation: