A cactus casts a

The melting point of substance X is -20 degrees Celsius and the boiling point is 90 degrees Celsius. How many Celsius degrees ar

Kazeer [188]

To find the distance between 2 numbers you must take the absolute value of the difference

|90-(-20)|
|110|
110

110 degrees celsius

3 0

2 years ago

Read 2 more answers

John is five years older than his sister. The product of their present ages is 150.

photoshop1234 [79]

Took 3 of us in grade 10 but johns present age is 77.5 and his sister is 72.5

5 0

2 years ago

A=1/4 and b=6.<br><br> −8ab=

podryga [215]

Answer:

When $a=\frac{1}{4}$ and $b=6$ :

$-8ab=-12$

Step-by-step explanation:

-8ab can be seen as -8×a×b. Insert the given values:

$-8*\frac{1}{4} *6$

Simplify multiplication from left to right:

$-8*\frac{1}{4} \\\\\frac{-8}{1} *\frac{1}{4} =\frac{-8}{4} =-2$

Insert and solve:

$-2*6=-12$

:Done

3 0

2 years ago

kim can mow the greens at the golf course twice as fast as shayla can. Working together, they can mow the greens in 4 hours. How

anyanavicka [17]

Answer: Kim can mow the greens alone in 6 hours.

Step-by-step explanation:

Let K be the rate Kim mows the greens, and S the rate for Shayla. The rates K and S will be in greens/hour.

We know they can mow 1 green in 4 hours. We can state this as a sum of their rates times the 4 hours equals one green:

(4 hours)*(K + S) = 1 green

We are told that K = 2S [Kim is twice as fast as Shayla]

Subsititute:

(4 hours)*(K + S) = 1 green

(4 hours)*(2S + S) = 1 green

4*(2S + S) = 1 green

12S = 1 green

Shalya's rate is 1 green/12 hours

Kim is twice as fast: K = 2S

Kim's rate is 1 green/6 hours.

8 0

2 years ago

] It is claimed that 42% of US college graduates had a mentor in college. For a sample of college graduates in Colorado, it was

Bad White [126]

Answer:

$z=\frac{0.480 -0.42}{\sqrt{\frac{0.42(1-0.42)}{1045}}}=3.930$

The p value for this case would be given by:

$p_v =P(z>3.930)=0.0000443$

For this case the p value is lower than the significance level so then we have enough evidence to reject the null hypothesis so then we can conclude that the true proportion is significantly higher than 0.42

Step-by-step explanation:

Information given

n=1045 represent the random sample selected

X=502 represent the college graduates with a mentor

$\hat p=\frac{502}{1045}=0.480$ estimated proportion of college graduates with a mentor

$p_o=0.42$ is the value that we want to test

z would represent the statistic

$p_v$ represent the p value

Hypothesis to test

We want to test if the true proportion is higher than 0.42, the system of hypothesis are.:

Null hypothesis: $p \leq 0.42$

Alternative hypothesis: $p > 0.42$

The statistic is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

Replacing the info we got:

$z=\frac{0.480 -0.42}{\sqrt{\frac{0.42(1-0.42)}{1045}}}=3.930$

The p value for this case would be given by:

$p_v =P(z>3.930)=0.0000443$

For this case the p value is lower than the significance level so then we have enough evidence to reject the null hypothesis so then we can conclude that the true proportion is significantly higher than 0.42

7 0

2 years ago