Which representation shows y as a function of x?

Rectangle A has length 12 and width 8. Rectangle B has length 15 and width 10. Rectangle C has length 30 and width 15.

never [62]

Vicki: 10 + 10 + 20 = 40

Johnny: 10 + 10 + 30 = 50

50 - 40 = 10 birds

5 0

3 years ago

A group of students estimated the length of one minute without reference to a watch or clock, and the times (seconds) are list

alexandr402 [8]

Complete Question

The complete question is shown on the first uploaded image

Answer:

Yes the students are reasonably good at estimating one minute

a

Option A is correct

b

The test statistics is $t = 0.354$

Step-by-step explanation:

From the question we are told that

The set of data is

68, 82 , 38 , 62 , 41, 25 , 57 , 64, 67, 47, 61, 71, 91, 87, 64

The population mean is $\mu = 60$

The level of significance is given as $\alpha = 0.01$

The critical value for this level of significance obtained from the normal distribution table is

$Z_{\alpha } = 2.33$

The null hypothesis is

$H_o : \mu = 60 \ seconds$

The alternative hypothesis is

$Ha : \mu \ne 60 \ seconds$

Generally the sample mean is mathematically represented as

$\= x = \frac{\sum x_i }{n }$

where n = 15

So

$\= x = \frac{ 68+ 82 + 38 + 62 + 41+ 25 + 57 + 64+67+ 47+ 61+ 71+ 91+ 87+ 64}{15}$

$\= x = 61.67$

The standard deviation is mathematically represented as

$\sigma =\sqrt{ \frac{ \sum (x_i - \= x )^2}{n} }$

substituting values

$\sigma =\sqrt{ \frac{ \sum (68-61.67)^2 + ( 82-61.67 )^2 + (38 -61.67)^2 + 62-61.67)^2 + (41-61.67)^2 +(25-61.67)^2 +( 57+61.67)^2 }{15} }$ $\sqrt{ \frac{ ( \cdot \cdot + ( 64-61.67)^2 + (67-61.67)^2 +(47-61.67)^2 + (61-61.67)^2+ (71-61.67)^2 + (91 -61.67)^2+( 87-61.67)^2 + (64-61.67)^2}{15} }$ => $\sigma = 18.23$

The test statistics is evaluated as

$t = \frac{\= x - \mu }{ \frac{\sigma }{\sqrt{n} } }$

substituting values

$t = \frac{61.67 -60 }{ \frac{18.23 }{\sqrt{ 15} } }$

$t = 0.354$

Now comparing the statistics and the critical value of the level of significance we see that the the test statistics is less than the critical value

Hence the we fail to reject the null hypothesis which mean that these times are from a population with a mean equal to 60 seconds

So we can state that yes the students are reasonably good at estimating one minute given that the sample mean is not far from the population mean

4 0

3 years ago

Today when Jeremy saw Mr. Winaki, the teacher said, “The amount of money in my wallet is more than $10, but less than $20. How m

OverLord2011 [107]

Answer:

Given that “The amount of money in my wallet is more than $10, but less than $20 " can be written in inequality form as

10 < w < 20 where " w" is the amount in the wallet .

1 ) Puzzle : -

Ryan is eating cookies . His mother ask how many cookies did he have .

He said number of cookies he ate is more than 19 and less than 41 .

We can write it in equality form as 19 < x < 41 where ' x ' is number of cookies Ryan have .

2) Puzzle :-

Number of steps a child take in an hour is more than 19 and less than 41 .

Write the situation in inequality form .

19 < p < 41 where " p " is the number of steps a child take in an hour .

3) Puzzle :-

Mother said to his child : " the number of coins in your piggy bank is more than 19 and less than 41 .

19 < c < 41 where " c " is number of coins in piggy bank .

7 0

4 years ago

Two-thirds of a number is equal to 20. What is the number?

IRISSAK [1]

Answer:

The number is 30

Step-by-step explanation:

Let x be the number

2/3 x = 20

Multiply each side by 3/2 to isolate x

3/2 *2/3x = 20*3/2

x = 30

4 0

4 years ago

Explain how you can round 25.691 to the greatest place.

Novosadov [1.4K]

The greatest place is the leftmost place. In 25.691, 2 is the greatest place and it is in the tens place. So, to round it to the nearest tens place, look at the number to the right of 2. Since that number is 5, change the 2 to 3. Then, change all numbers except for the 2 to 0, making it 30.000. You can also write 30 and ignore the zeros to the right of the decimal.

8 0

4 years ago