All categories

3 years ago

2/5 and 3/8 common denominator

Mathematics

2 answers:

Svetlanka [38]3 years ago

8 0

Answer:

it's 40

Step-by-step explanation:

$\frac{2}{5} \frac{ \times }{ \times } \frac{8}{8} = \frac{16}{40} \\ \frac{3}{8} \frac{ \times }{ \times } \frac{5}{5} = \frac{15}{40}$

so the common denominator is 40

Nat2105 [25]3 years ago

6 0

Answer:

Step-by-step explanation:

The common denominator = 5×8

= 40

You might be interested in

Equivalent fraction to 42\63

Nikitich [7]

Answer:

2/3

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

What is 9x-5x ????i need help

Dima020 [189]

Hi there!

Answer:

=4x

Step-by-step explanation:

Distributive property: ⇒ a(b+c)=ab+ac

You had to add similar elements.

9x-5x=4x

5x+4x=9x

9x-4x=5x

final answer: =4x

Hope this helps!

-Charlie

Have a great day!

4 0

4 years ago

The temperature at a ski resort was 12°F at 5:00 A.M. If the temperature increased by 1.5°F each hour, what would be the tempera

Mariana [72]

The correct answer is:

22.5° F.

Explanation:

The temperature increases 1.5° per hour. From 5:00 AM to 12:00 PM is 12-5 = 7 hours. This makes an increase of 1.5(7) = 10.5°.

The temperature started at 12°F; increasing by 10.5° gives us

12+10.5 = 22.5°F.

3 0

3 years ago

Branliest and Extra Points will be given!!! No explanation needed just the answer plz.

Hitman42 [59]

Right triangle, Pythagorean Theorem:

c² = a² + b²

a=8, b=9

c² = 8² + 9² = 64 + 81 = 145

c = √145 inches

That's the exact answer but they want us to ruin it with an approximation.

c ≈ 12.041594578792296 inches

Answer: 12

3 0

4 years ago

In a simple random sample of 14001400 young people, 9090% had earned a high school diploma. Complete parts a through d below.

ratelena [41]

Answer:

(a) The standard error is 0.0080.

(b) The margin of error is 1.6%.

(c) The 95% confidence interval for the percentage of all young people who earned a high school diploma is (88.4%, 91.6%).

(d) The percentage of young people who earn high school diplomas has increased.

Step-by-step explanation:

Let p = proportion of young people who had earned a high school diploma.

A sample of n = 1400 young people are selected.

The sample proportion of young people who had earned a high school diploma is:

$\hat p=0.90$

(a)

The standard error for the estimate of the percentage of all young people who earned a high school diploma is given by:

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

Compute the standard error value as follows:

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

$=\sqrt{\frac{0.90(1-0.90)}{1400}}\\$

$=0.008$

Thus, the standard error for the estimate of the percentage of all young people who earned a high school diploma is 0.0080.

(b)

The margin of error for (1 - α)% confidence interval for population proportion is:

$MOE=z_{\alpha/2}\times SE_{\hat p}$

Compute the critical value of z for 95% confidence level as follows:

$z_{\alpha/2}=z_{0.05/2}=z_{0.025}=1.96$

Compute the margin of error as follows:

$MOE=z_{\alpha/2}\times SE_{\hat p}$

$=1.96\times 0.0080\\=0.01568\\\approx1.6\%$

Thus, the margin of error is 1.6%.

(c)

Compute the 95% confidence interval for population proportion as follows:

$CI=\hat p\pm MOE\\=0.90\pm 0.016\\=(0.884, 0.916)\\\approx (88.4\%,\ 91.6\%)$

Thus, the 95% confidence interval for the percentage of all young people who earned a high school diploma is (88.4%, 91.6%).

(d)

To test whether the percentage of young people who earn high school diplomas has increased, the hypothesis is defined as:

H₀: The percentage of young people who earn high school diplomas has not increased, i.e. p = 0.80.

Hₐ: The percentage of young people who earn high school diplomas has not increased, i.e. p > 0.80.

Decision rule:

If the 95% confidence interval for proportions consists the null value, i.e. 0.80, then the null hypothesis will not be rejected and vice-versa.

The 95% confidence interval for the percentage of all young people who earned a high school diploma is (88.4%, 91.6%).

The confidence interval does not consist the null value of p, i.e. 0.80.

Thus, the null hypothesis is rejected.

Hence, it can be concluded that the percentage of young people who earn high school diplomas has increased.

8 0

3 years ago