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3 years ago

13

you receive an allowance of a penny the first day of the month and the amount you receive doubles every day for the rest of the

month assume the month has 30 days how much would your allowance be after one month?

1 answer:

nignag [31]3 years ago

8 0

Answer:

56

Step-by-step explanation:

You might be interested in

kareem took 5 hours to drive 470km from Sudbury to Brantford. for part of the trip he drove at 100km/h. for the rest of the trip

alexira [117]

Answer:

He drove 200 km at 100 km/h and 270 km at 90 km/h

Step-by-step explanation:

Distance = Speed × Time

<em>Assume that Kareem drove at 100 km/h for x hour</em>

∵ Kareem drove at 100 km/h for x hours

∴ He drove a distance = 100 × x

∴ He drove a distance = 100 x km

∵ He took 5 hours in whole trip

- Subtract x from 5 to find the time that he took in the rest

of the trip

∴ The time of the rest of the trip = 5 - x hours

∵ For the rest of the trip he drove at 90 km/h

∴ He drove a distance = 90 × (5 - x)

∴ He drove a distance = 450 - 90 x

∵ He drove 470 km in whole trip

- Add the two distance and equate the sum by 470

∴ 100 x + 450 - 90 x = 470

- Add the like terms in the left hand side

∴ 10 x + 450 = 470

- Subtract 450 from both sides

∴ 10 x = 20

- Divide both sides by 10

∴ x = 2

<em>Substitute the value of x in each distance to find the distance of each part</em>

∵ The distance of the first part = 100 x

∴ The distance of the first part = 100(2)

∴ The distance of the first part = 200 km

∵ The distance of the second part = 450 - 90 x

∴ The distance of the second part = 450 - 90(2) = 450 - 180

∴ The distance of the second part = 270 km

He drove 200 km at 100 km/h and 270 km at 90 km/h

4 0

3 years ago

In a college student poll, it is of interest to estimate the proportion p of students in favor of changing from a quarter-system

Contact [7]

Answer:

n=206

Step-by-step explanation:

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".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by:

$t_{\alpha/2}=-2.58, t_{1-\alpha/2}=2.58$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.09$ , we can use as prior estimate of p 0.5, since we don't have any other info provided, and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.09}{2.58})^2}=205.44$

And rounded up we have that n=206

3 0

3 years ago

Draw a diagram that shows 1/5 times 30 equals 6

vodomira [7]

1 30 30
-- x ---- = ---- ---> 30/5 = 6
5 1 5

30 is a full number but it can turn into a fraction. The whole number (30) will be the numerator (the top number) and 1 is basically "the quantitative number" aka the denominator (the bottom number).

The final result of this problem is 30 over 5. Which you can divide. Always divide the numerator to the denominator to get your answer (for this kind of problem).

7 0

3 years ago

The sum of two numbers is 43 and the difference is 3. What are the numbers?

frutty [35]

Answer:

1st number=(43-3)÷2=20

2nd number= 43-20=23

Numbers: 20,23

6 0

3 years ago

Read 2 more answers

Please answer it correctly please show your work and I need it right now please

madam [21]

Answer:

-61.83

Step-by-step explanation:

Given expression is $\frac{7}{-2.5+8.5} +\frac{0.6\times(8+13)}{-0.2}$

We know that 0.6 is 3 times 0.2 so we can cancel 0.6

Also 8.5-2.5 = 6

⇒ $\frac{7}{6}-\frac{3\times21}{1}$

⇒ $\frac{7}{6}-63 = \frac{7-6\times 63}{6} = -\frac{371}{6}$ = -61.83

4 0

3 years ago