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2 years ago

Can someone help me fast -2 1/3 - (-5

Mathematics

1 answer:

lisov135 [29]2 years ago

5 0

Answer:

your answer is positive 8/3

Step-by-step explanation:

When you are subtracting something by a negative number, it is the same as adding by a positive. For example, this equation would be solved like:

-2 1/3 + 5

Instead of -2 1/3 - (-5)

Hope that helps!

You might be interested in

The average THC content of marijuana sold on the street is 9.3%. Suppose the THC content is normally distributed with standard d

velikii [3]

Answer:

a) $X \sim N(9.3,1)$

b) $P(X>9.2)=P(\frac{X-\mu}{\sigma}>\frac{9.2-\mu}{\sigma})=P(Z>\frac{9.2-9.3}{1})=1-P(Z$

c) The value of height that separates the bottom 75% of data from the top 25% is 9.9745.

Step-by-step explanation:

1) 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".

2) Part a

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

$X \sim N(9.3,1)$

Where $\mu=9.3$ and $\sigma=1$

3) Part b

We are interested on this probability

$P(X>9.2)$

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:

$P(X>9.2)=P(\frac{X-\mu}{\sigma}>\frac{9.2-\mu}{\sigma})=P(Z>\frac{9.2-9.3}{1})=1-P(Z$

4) Part c

For this part we want to find a value a, such that we satisfy this condition:

$P(X>a)=0.25$ (a)

$P(X$ (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.75 of the area on the left and 0.25 of the area on the right it's z=0.6745. On this case P(Z<0.6745)=0.75 and P(z>0.6745)=0.25

If we use condition (b) from previous we have this:

$P(X$

$P(Z$

But we know which value of z satisfy the previous equation so then we can do this:

$z=0.6745$

And if we solve for a we got

$a=9.3 +1*0.6745=9.9745$

So the value of height that separates the bottom 75% of data from the top 25% is 9.9745.

8 0

3 years ago

How old am I if 500 reduced by 2 times my age is 322?

Yuliya22 [10]

Answer:

You are 89 years old.

Step-by-step explanation:

First I subtracted 322 from 500 which got me 178. Then I finally did 178 divided by 2 which got me 89.

Hope this helps you! :)

5 0

3 years ago

The cookie factory has a fixed cost of $300 per month plus $.45 for each cookie sold. Each cookie sells for $.95. How many cooki

anygoal [31]

Answer: the number of cookies sold must be greater than or equal to 800

Step-by-step explanation:

Let x represent the number of cookies made and sold in a month.

The cookie factory has a fixed cost of $300 per month plus $.45 for each cookie. This means that the total cost of producing x cookies in a month would be

300 + 0.45x

Each cookie sells for $.95. This means that the total revenue from selling x cookies would be

0.95x

Profit = Revenue - cost

Therefore, the number of cookies that must be sold during one month for the profit to be at least $100 would be

0.95x - (300 + 0.45x) ≥ 100

0.95x - 300 - 0.45x ≥ 100

0.95x - 0.45x ≥ 100 + 300

0.5x ≥ 400

x ≥ 400/0.5

x ≥ 800

7 0

3 years ago

92.4 is 150% of what number?

Ad libitum [116K]

1. We assume, that the number 92.4 is 100% - because it's the output value of the task.
2. We assume, that x is the value we are looking for. 
3. If 92.4 is 100%, so we can write it down as 92.4=100%. 
4. We know, that x is 150% of the output value, so we can write it down as x=150%. 
5. Now we have two simple equations:
1) 92.4=100%
2) x=150%
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
92.4/x=100%/150%
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for what is 150% of 92.4

92.4/x=100/150
(92.4/x)*x=(100/150)*x - we multiply both sides of the equation by x
92.4=0.666666666667*x - we divide both sides of the equation by (0.666666666667) to get x
92.4/0.666666666667=x 
138.6=x 
x=138.6

now we have: 
150% of 92.4=138.6

3 0

4 years ago

Read 2 more answers

Matt has 3 dark t-shirts and 6 white t-shirts. First, he will close his eyes to select a

valina [46]

Answer:

around 73-89%

Step-by-step explanation:

Hope this helps!

8 0

3 years ago