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MA_775_DIABLO [31]
2 years ago
15

In a bag, there are a total of 50 dimes and quarters. 40% of the coins are quarters and 35% of the quarters are on heads. How ma

ny of the quarters are on tails? ​
Mathematics
1 answer:
erik [133]2 years ago
7 0

Answer:

13 quarters must be tails.

Step-by-step explanation:

Number of quarters = 40% of 50 coins

Number of quarters = 40/100 * 50 = 20 coins which are quarters.

35% of these 20 quarters on heads. We can proceed in 2 ways from here.

We can actually find the number of quarters that are on heads.

35/100 * 20 = 7 quarters are showing heads.

Since the other quarters must be tails 20 - 7 = 13 quarters must be tails.

The other way to do it is to realize that if 35% of the coins are heads, 65% of the coins must be tails 20 * 65/100 = 13 which is a bit more direct.

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Can anyone help me find the value pls?
Flauer [41]

The inside angle for B, which is labeled x is the same as the outside angle of D which is labeled as 72, so we know x = 72.

In a parallelogram two angles next to each other equal 180, so angle A and angle B equal 180.

We know B = 72, so A = 180-72 = 108

Angle A is divided in 2 by angle y, so y = 108/2 = 54

Answers: x = 72

Y = 54

4 0
2 years ago
Choose the correct simplification of the expression (−2x 8y)(9x − 3y).−18x2 78xy − 24y218x2 78xy − 24y2−18x2 − 78xy 24y2−18x2 72
Sedbober [7]
The last one -18x2 72xy -24y2
3 0
3 years ago
Bob Nale is the owner of Nale’s Quick Fill. Bob would like to estimate the mean number of gallons of gasoline sold to his custom
ira [324]

Answer:

a) The best estimator for the population mean is given by the sample mean \hat \mu = \bar X = 5.70

b) The 99% confidence interval would be given by (4.969;6.431)    

c) We are 99% confident that the true mean for th number of gallons of gasoline  sold to his customers is between 4.969 and 6.431.

Step-by-step explanation:

1) Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

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".

\bar X represent the sample mean for the sample  

\mu population mean (variable of interest)

\sigma=1.9 represent the population standard deviation

n=45 represent the sample size  

2) Part a

The best estimator for the population mean is given by the sample mean \hat \mu = \bar X = 5.70

3) Part b. Develop a 99 percent confidence interval for the population mean.

The confidence interval for the mean is given by the following formula:

\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}   (1)

Since the Confidence is 0.95 or 95%, the value of \alpha=0.01 and \alpha/2 =0.005, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that z_{\alpha/2}=2.58

Now we have everything in order to replace into formula (1):

5.7-2.58\frac{1.9}{\sqrt{45}}=4.969    

5.7+2.58\frac{1.9}{\sqrt{45}}=6.431

So on this case the 99% confidence interval would be given by (4.969;6.431)    

4) Part c. Interpret the meaning of part (b).

On this case we can say this: We are 99% confident that the true mean for th number of gallons of gasoline  sold to his customers is between 4.969 and 6.431.

4 0
3 years ago
6x-58+2x+4=5x<br>find the value of x
mariarad [96]
You pass the x in one side and numbers to the other side
8x-5x=58-4
add and subtract
3x=54
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7 0
3 years ago
State whether the given equation or function is linear. Write yes or no. Explain your reasoning. f(x) = 7x2 + 4
vagabundo [1.1K]

For this case we have the following function:

f (x) = 7x ^ 2 + 4

By definition, we have that a linear equation is of the form y = mx + b

On the other hand, a quadratic equation is of the formy = ax ^ 2 + bx + c

Then, the given equation is not a linear equation, it is not of the form y = mx + b

Answer:

No, the equation is not linear. It is not of the form f (x) = mx + b.

4 0
3 years ago
Read 2 more answers
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