All categories

3 years ago

If y varies directly as x, and y is 20 when x is 4, what is the constant of variation for this relation?

Mathematics

1 answer:

yuradex [85]3 years ago

3 0

Y
y=ax
where a is a constant of proportionality;
y=20, x=4
20=4a
a=20/4
a=5
y=5x
The constant of variation is 5

You might be interested in

Incomplete substance for an expression that doesn't mean anything and needs to be solved

Alona [7]

Variable is the answer because it needs to be solved and doesnt mean anything

8 0

3 years ago

The poll found that 38% of a random sample of 1012 American adults said they believe in ghosts. What is the lower bound for a 90

Brrunno [24]

Answer:

The lower bound for a 90% confidence interval for the percentage of all American adults who believe in ghosts is 0.3549

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

$n = 1012, \pi = 0.38$

90% confidence level

So $\alpha = 0.1$ , z is the value of Z that has a pvalue of $1 - \frac{0.1}{2} = 0.95$ , so $Z = 1.645$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.38 - 1.645\sqrt{\frac{0.38*0.62}{1012}} = 0.3549$

The lower bound for a 90% confidence interval for the percentage of all American adults who believe in ghosts is 0.3549

6 0

4 years ago

Help my teacher is mean i have to get a score of 80% or higher

coldgirl [10]

Answer:

26%

Step-by-step explanation:

26 out of 100 orange squares are coloured in. To find the percentage of the shape you take:

Number of coloured sqaures / Total number of squares x 100 = %

= (26/100) x 100

= (0.26) x 100

= 26%

4 0

3 years ago

Read 2 more answers

A butcher purchases 50 chicks at the rate of Ts.60 per chick.10 of them died and he sold remaining chicks at the rate of Rs.80 p

Romashka-Z-Leto [24]

Answer: 6.25%

Step-by-step explanation:

50 chicks were purchased at Rs. 60. The total cost of the chicks is:

= 50 * 60

= Rs. 3,000

10 of the chicks died which means the farmer was left with 40 chicks.

These chicks are sold at Rs. 80. Total revenue from the sales are:

= 40 chicks * 80

= Rs. 3,200

The profit is:

= 3,200 - 3,000

= Rs. 200

The percentage is:

= Profit / Revenue

= 200 / 3,200

= 6.25%

3 0

3 years ago

A.-8<br> B.12<br> C.-20<br> D.32

11Alexandr11 [23.1K]

Answer:

C. -20

Step-by-step explanation:

Step 1: $\frac{mn}{p}$ + (-n) Write down equation

Step 2: $\frac{2(12)}{-3}$ + (-12) insert values into equation

Step 3: $\frac{24}{-3}$ - 12 Simplifying fraction and parentheses

Step 4: -8 - 12 Simplifying fraction 24/-3 = -8

Answer: -20

5 0

3 years ago