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2 years ago

Elsa had a negative bank account

Mathematics

1 answer:

Softa [21]2 years ago

8 0

Answer:

it will take her 12 days

Step-by-step explanation:

you do this problem by subtracting the 180 form 720 thne dividing by how much she will be adding every day

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1/4 + 5/8 + 1/8 + 1/4 + 1/4 + 1/4 + 3/4 + 3/4

zysi [14]

1/4=2/8 and 3/4=6/8... common denominator
2/8+5/8+1/8+2/8+2/8+2/8+6/8+6/8=26/8=13/4=3 1/4

7 0

2 years ago

Read 2 more answers

Find the standard deviation of 21, 31, 26, 24, 28, 26

Vesnalui [34]

Given the dataset

$x = \{21,\ 31,\ 26,\ 24,\ 28,\ 26\}$

We start by computing the average:

$\overline{x} = \dfrac{21+31+26+24+28+26}{6}=\dfrac{156}{6}=26$

We compute the difference bewteen each element and the average:

$x-\overline{x} = \{-6,\ 5,\ 0,\ -2,\ 2,\ 0\}$

We square those differences:

$(x-\overline{x})^2 = \{36,\ 25,\ 0,\ 4,\ 4,\ 0\}$

And take the average of those squared differences: we sum them

$\displaystyle \sum_{i=1}^n (x-\overline{x})^2=36+25+4+4+0+0=69$

And we divide by the number of elements:

$\displaystyle \sigma^2=\dfrac{\sum_{i=1}^n (x-\overline{x})^2}{n} = \dfrac{69}{6} = 11.5$

Finally, we take the square root of this quantity and we have the standard deviation:

$\displaystyle\sigma = \sqrt{\dfrac{\sum_{i=1}^n (x-\overline{x})^2}{n}} = \sqrt{11.5}\approx 3.39$

8 0

2 years ago

What's the answer to this question

Cerrena [4.2K]

10.1 x 8 - 6 = 80.8 - 6 = 74.8
u just had to substitute the variables

3 0

2 years ago

To rationalize the denominator of 2/square 13+ squared 11 , you should multiply the expression by which fraction?

eimsori [14]

Answer:

You should multiply the expression by $\frac{\sqrt{13}-\sqrt{11}}{\sqrt{13}-\sqrt{11}}$

Explanation:

To rationalize any expression, you must multiply it by its conjugate. A conjugate is defined as a similar expression to the original one but with an opposite sign

This means that:

The conjugate of a + b would be a - b

Now, the given expression is $\frac{2}{\sqrt{13}+\sqrt{11}}$

Consider the denominator:

From the above, we can conclude that the conjugate of $\sqrt{13}+\sqrt{11}$ is $\sqrt{13}-\sqrt{11}$

And, remember that we need to keep the value of the expression unchanged. This means that we must multiply both the numerator and the denominator by the same value

Therefore:

You should multiply the expression by $\frac{\sqrt{13}-\sqrt{11}}{\sqrt{13}-\sqrt{11}}$ in order to rationalize the denominator

Hope this helps :)

5 0

2 years ago

Read 2 more answers

Your friend decides to flip a coin repeatedly to analyze whether the probability of a head on each flip is 1/2. He flips the coi

Phoenix [80]

Answer:

Step-by-step explanation:

Given that a friend flips a coin 10 times and observes head 7 times. So he concludes Probability of head =0.1

This is wrong because

i) Just making 10 trials and coming to conclusion is wrong. Trials should be large to get accurate estimate

ii) The way he threw the coin may be biased so differrent persons should flip and get results for larger trials

iii) External influences such as air, any other disturbance is not considered here.

To avoid all these sampling fluctuations number of trials should be increased with different situations and times.

6 0

2 years ago