20 total balls:

5 are black

17 NOT yellow

12 NOT green

20-17 = 3

20-12 = 8

5 Black + 3 yellow + 8 green = 16 balls

20 total balls - 16 balls = 4 blue balls

Ewa has 4 blue balls.

4 0

3 years ago

What is the measure of angle x?

tankabanditka [31]

Answer:

could you upload a picture?

Step-by-step explanation:

7 0

3 years ago

Construct a 95% confidence interval for the population mean, μ. Assume the population has a normal distribution. A random sample

GuDViN [60]

Answer: $(628.48,\ 661.52)$

Step-by-step explanation:

Given : Sample size : $n=16$ , which is a small sample (, 30) so we use t-test.

Sample mean : $\overline{x}=645 \text{ hours}$

Standard deviation : $\sigma = 31 \text{ hours}$

Significance level : $\alpha=1-0.95=0.05$

Critical value : $t_{n-1,\alpha/2}=2.131$

The confidence interval for population mean is given by :-

$\overline{x}\pm t_{n-1,\alpha/2}\dfrac{\sigma}{\sqrt{n}}\\\\=645\pm(2.131)\dfrac{31}{\sqrt{16}}\\\\\approx645\pm16.52\\\\=(645-16.52,\ 645+16.52)\\\\=(628.48,\ 661.52)$

Hence, a 95% confidence interval for the population mean $\mu$ = $(628.48,\ 661.52)$

6 0

3 years ago