How long is the Yangtze river

Nifal earned 9$ for washing two cars .He recived $1 more for the second car.How much was he paid for washing each car?Which two

Sveta_85 [38]

Answer:

Nifal received $ 4 for washing the first car.

Nifal received $ 5 for washing the second car.

4 and 5 have a sum of 9.

Step-by-step explanation:

The problem can be rewritten as follows: Find the sum of two consecutive entire numbers equal to 9. That is:

$x + y = 9$

$y = x+1$

Then, by eliminating y:

$x + (x+1) = 9$

$2\cdot x + 1 = 9$

Now, let is clear $x$ :

$2\cdot x = 8$

$x = 4$

Nifal received $ 4 for washing the first car.

The earning for the second car is: ( $x = 4$ )

$y = x +1$

$y = 4 + 1$

$y = 5$

Nifal received $ 5 for washing the second car.

4 and 5 have a sum of 9.

8 0

2 years ago

A College Alcohol Study has interviewed random samples of students at four-year colleges. In the most recent study, 494 of 1000

Vinil7 [7]

Answer:

The 95% confidence interval for the difference between the proportion of women who drink alcohol and the proportion of men who drink alcohol is (-0.102, -0.014) or (-10.2%, -1.4%).

Step-by-step explanation:

We want to calculate the bounds of a 95% confidence interval of the difference between proportions.

For a 95% CI, the critical value for z is z=1.96.

The sample 1 (women), of size n1=1000 has a proportion of p1=0.494.

$p_1=X_1/n_1=494/1000=0.494$

The sample 2 (men), of size n2=1000 has a proportion of p2=0.552.

$p_2=X_2/n_2=552/1000=0.552$

The difference between proportions is (p1-p2)=-0.058.

$p_d=p_1-p_2=0.494-0.552=-0.058$

The pooled proportion, needed to calculate the standard error, is:

$p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{494+552}{1000+1000}=\dfrac{1046}{2000}=0.523$

The estimated standard error of the difference between means is computed using the formula:

$s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.523*0.477}{1000}+\dfrac{0.523*0.477}{1000}}\\\\\\s_{p1-p2}=\sqrt{0.000249+0.000249}=\sqrt{0.000499}=0.022$

Then, the margin of error is:

$MOE=z \cdot s_{p1-p2}=1.96\cdot 0.022=0.0438$

Then, the lower and upper bounds of the confidence interval are:

$LL=(p_1-p_2)-z\cdot s_{p1-p2} = -0.058-0.0438=-0.102\\\\UL=(p_1-p_2)+z\cdot s_{p1-p2}= -0.058+0.0438=-0.014$

The 95% confidence interval for the difference between proportions is (-0.102, -0.014).

7 0

2 years ago

The graph of a function f is shown below. Find f(-1).

VMariaS [17]

Isn’t it 1 / 1 ?or something like that is positive for sure

4 0

3 years ago

Ella and three friends run in a relay that is 14 miles long.Each person runs equal parts of the race.How many miles does each pe

sergeinik [125]

Each Person Runs: 3.5 miles.
14÷4= 3.5.

3 0

2 years ago

Read 2 more answers

A ball is dropped from a height of 14 ft. The elasticity of the ball is such that it always bounces up one-third the distance it

Korvikt [17]

Answer:

Hello,

742/27 (ft)

Step-by-step explanation:

$h_1=14\\\\h_2=\dfrac{14}{3} \\\\h_3=\dfrac{14}{9} \\\\h_4=\dfrac{14}{27} \\\\$

$d=14+2*\dfrac{14}{3} +2*\dfrac{14}{9} +2*\dfrac{14}{27} \\=14*(1+\dfrac{1}{3}+\dfrac{2}{9} +\dfrac{2}{27} )\\=14*\dfrac{53}{27} \\=\dfrac{742}{27} \\$

5 0

2 years ago