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3 years ago

How many odd positive integers greater than 50 and less than 140 are there?

Mathematics

2 answers:

valentinak56 [21]3 years ago

8 0

Step-by-step explanation:

there are 45 odd numbers

tangare [24]3 years ago

7 0

Answer:

Step-by-step explanation:

to figure this out, lets first subtract 50 from 140 so we can start at 0, it will be easier to calculate and we will get the same result

140 - 50 = 90

then since theres 1 odd intager for every even intager in an even set of numbers, we can divide 90 by 2 to get the amount of odd intagers

90 / 2 = 45

if you start at 0, 50, or even 5 million, as long as the difference between the two thresholds stay the same, you will get the same result

You might be interested in

What is the approximate total percent off when you buy something at "An extra 20% off of 40% off"?

Georgia [21]

Answer:

48%

Step-by-step explanation:

let's say the initial price of an item is $100

if you take 40% off then you pay only $60

now if you take 20% off 60 you pay $48

$48 is 48% of 100

8 0

3 years ago

Suppose the life of a particular brand of calculator battery is approximately normally distributed with a mean of 75 hours and a

shepuryov [24]

Answer:

a) $P(X$

And we can find this probability using the normal standard table or excel:

$P(z$

b) $P(X>77)=P(\frac{X-\mu}{\sigma}>\frac{77-\mu}{\sigma})=P(Z>\frac{77-75}{10})=P(z>0.2)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.2)=1-P(Z$

c) $z = \frac{70-75}{\frac{10}{\sqrt{16}}}= -2$

$z = \frac{80-75}{\frac{10}{\sqrt{16}}}= 2$

And we can find this probability with this difference:

$P(-2$

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the life of a particular brand of a population, and for this case we know the distribution for X is given by:

$X \sim N(75,10)$

Where $\mu=75$ and $\sigma=10$

Part a

We are interested on this probability

$P(X$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(X$

And we can find this probability using the normal standard table or excel:

$P(z$

Part b

$P(X>77)=P(\frac{X-\mu}{\sigma}>\frac{77-\mu}{\sigma})=P(Z>\frac{77-75}{10})=P(z>0.2)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.2)=1-P(Z$

Part c

For this case we select a sample size of n =16. and we want this probability:

$P(70 < \bar X$

We know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And we can find the z scores for the limits like this:

$z = \frac{70-75}{\frac{10}{\sqrt{16}}}= -2$

$z = \frac{80-75}{\frac{10}{\sqrt{16}}}= 2$

And we can find this probability with this difference:

$P(-2$

6 0

3 years ago

karen is preparing for her younger sisters birthday party she divides a jar of lollipops evenly among 6 goodie bags. Each bag en

Zina [86]

I think I’m correct if I understood your problem correctly. 4•6=x

X represents the total number of lollipops that were originally in the jar

7 0

3 years ago

Choose the equivalent system of linear equations that will produce the same solution as the one given below. (1 point) 4x − 2y =

goldenfox [79]

Answer:

<h3>Option d) 4x + 2y = 10 and 8x = 16 is correct</h3><h3>Therefore 4x + 2y = 10 and 8x = 16 equations have equivalent solution (2,1) is same as the solution of given linear system of equations</h3>

Step-by-step explanation:

Given equations are

$4x-2y=6\hfill (1)$

$2x+y=5\hfill (2)$

<h3>To find the the equivalent system of linear equations that will produce the same solution as for the given equation :</h3>

First find the solution to the given system of equations by elimination method

Multiply the equation (2) into 2 we get

$4x+2y=10\hfill (3)$

Now adding the equations (1) and ( 3) we get

$4x-2y=6$

$4x+2y=10$

_______________

$8x=16$

$x=\frac{16}{8}$

x=2

Therefore the value of x is 2

Substitute the value of x in equation (1) we get

$4(2)-2y=6$

$8-2y=6$

$-2y=6-8$

$-2y=-2$

$y=\frac{-2}{-2}$

y=1

Therefore the value of y is 1

Therefore the solution to the given system of equations is (2,1)

<h3>Now to find the equivalent system of equations have same solution (2,1)</h3>

Verify the equations $4x+2y=10\hfill (4)$ and 8x = 16

From 8x=16

$x=\frac{16}{8}$

x=2

Therefore the value of x is 2

Substitute x=2 in equation (4) we get

4(2)+2y=10

8+2y=10

2y=10-8

2y=2

$y=\frac{2}{2}$

y=1

Therefore the value of y is 1

Therefore the solution is (2,1)

<h3>Therefore option d) 4x + 2y = 10 and 8x = 16 equations have equivalent solution (2,1) is same as the solution of given linear system of equations </h3>

3 0

3 years ago

−6(x+7)=−4x−2 how many solutions

yaroslaw [1]

Answer: There is one solution, -20

Step-by-step explanation:

$-6(x+7)=-4x-2\\\\Distribute\\\\-6x-42=-4x-2\\\\Add(6x)\\\\-42=2x-2\\\\Add(2)\\\\-40=2x\\\\x=-20$