Given that we have the change in temperature over 7 hours and we are looking for the change over 1 hour, we can divide the total change in temperature by 7. Thus, the change in temperature would be $\frac{42}{7} C^{\circ}$ .

Additionally, this can be solved by equations:

$\dfrac{42 \,\textrm{C}^{\circ}}{7 \,\textrm{hours}} = \dfrac{x \,\textrm{C}^{\circ}}{1 \,\textrm{hour}}$

$1 \,\textrm{hour} \cdot \dfrac{42 \,\textrm{C}^{\circ}}{7 \,\textrm{hours}} = x \,\textrm{C}^{\circ}$

$\dfrac{42}{7} \,\textrm{C}^{\circ} = x \,\textrm{C}^{\circ}$

$\dfrac{42}{7} = x$

By using two different methods, we can determine that the change each hour was equal to 42/7 C° per hour.

6 0

3 years ago

A music buff wants to estimate the percentage of students at a midwestern university who believe that elvis is still alive. how

gulaghasi [49]

Since we are not given any information about the proportion, we will assume the sample proportion to be 0.50

so,
p = 0.50
The Error is 10% percentage point. This means that on either side of the population proportion the error is 5% so E = 0.05
z = 1.645 (Z value for 90% confidence interval)

The margin of error for population proportion is calculated as:

$E=z* \sqrt{ \frac{p(1-p)}{n} } \\ \\ 
 \frac{E}{z} = \sqrt{ \frac{p(1-p)}{n} } \\ \\ 
( \frac{E}{z} )^{2}= \frac{p(1-p)}{n} \\ \\ 
n= p(1-p)* (\frac{z}{E})^{2} \\ \\ 
n=271$

This means 271 students should be included in the sample

5 0

3 years ago

PLZ HURRY IT'S URGENT!!

Ksenya-84 [330]

The answer would be 40
-4(-2) = 8
8(5) = 40

7 0

3 years ago

Given: f(x) = 2x4 +10 and g(x) = 4x – 15 What is the value of g f (x)?​

Given: f(x) = 2x4 +10 and g(x) = 4x – 15 What is the value of g f (x)?