Survey Time Who is at school? Who is working online from home?

juin [17]

Well I came up with the answer
3c^2 + 3.25c - 2.25

Not sure if this is correct but I hope it is and that it helps!

Have an amazing day✨❤️

6 0

3 years ago

A set of city temperatures in April are normally distributed with a mean of 19.7 degrees Celsius and a standard deviation of 2 d

Sati [7]

Answer:

19.77% of average city temperatures are higher than that of Cairo

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question, we have that:

$\mu = 19.7, \sigma = 2$

What percentage of average city temperatures are higher than that of Cairo?

This is 1 subtracted by the pvalue of Z when X = 21.4.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{21.4 - 19.7}{2}$

$Z = 0.85$

$Z = 0.85$ has a pvalue of 0.8023

1 - 0.8023 = 0.1977

19.77% of average city temperatures are higher than that of Cairo

6 0

3 years ago

How to do a dilation factor in geometry

Ostrovityanka [42]

Hello!

To find the dilation factor you find what figure 1 was multiplied by to get figure 2

Hope this helps!

8 0

3 years ago

Find The Missing Exponent (b^2)_=b^-6

lisov135 [29]

There answer should well be -24 you take the sign from the greater digit and if it's different digits you subtract but I'm this case were dividing and -24 ÷4 = -6

8 0

3 years ago

4cos^2(theta)+2sin(theta)=2

DedPeter [7]

Answer:

The value of given expression i.e Ф is 90° and - 30°

Step-by-step explanation:

Given as :

4 cos²Ф + 2 sinФ = 2

∵ sin²Ф + cos²Ф = 1 , so , cos²Ф = 1 - sin²Ф

Or, 4 ( 1 - sin²Ф ) + 2 sinФ = 2

Or, 4 - 4 sin²Ф + 2 sinФ = 2

or, 4 sin²Ф - 2 sinФ - 4 + 2 = 0

or, 4 sin²Ф - 2 sinФ - 2 = 0

or, 2 sin²Ф - sinФ - 1 = 0

or, 2 sin²Ф - 2 sinФ + sinФ - 1 = 0

Or, 2 sinФ ( sinФ - 1 ) + 1 ( sinФ - 1 ) = 0

∴ ( sinФ - 1 ) ( 2 sinФ + 1 ) = 0

i.e ( sinФ - 1 ) = 0 And ( 2 sinФ + 1 ) = 0

since ( sinФ - 1 ) = 0

So, sinФ = 1

Or, Ф = $sin^{-1}(1)$ = 90°

And ( 2 sinФ + 1 ) = 0

Or, 2 sinФ = - 1

Or, sinФ = - $\frac{1}{2}$

Or, Ф = $sin^{-1}(-\frac{1}{2})$ = - 30°

Hence the value of given expression i.e Ф is 90° and - 30° Answer

6 0

3 years ago