$\overline{x}\pm t_{\alpha/2}\dfrac{s}{\sqrt{n}}$ , where $\overline{x}$ = sample mean, n= sample size, s= sample standard deviation, $t_{\alpha/2}$ = two-tailed t value.

As per given: n= 10

degree of freedom : df = n-1=9

$\overline{x}=242.6\\\\s=73.33\\\\\alpha=5\%=0.05$

Critical t-value : $t_{\alpha/2,df}=t_{0.05/2,9}=t_{0.025,9}=2.2622$

So, the 95 percent confidence interval estimate for the mean :

$242.6\pm (2.2622)\dfrac{73.33}{\sqrt{10}}\\\\=242.6\pm (2.2622)(23.19)\\\\\approx242.6\pm52.46\\\\=(242.6-52.46,\ 242.6+52.46)\\\\=(190.14,\ 295.06)$

The 95 percent confidence interval estimate for the mean:(190.14, 295.06)

8 0

3 years ago

15% of 72 is ______

BigorU [14]

Answer: convert 15% to a decimal. 0.15 times 75 is 11.25

Converting Percentages to Decimals

Easiest—divide by 100: The simplest way to convert a percentage to a decimal is to divide the number (in percentage format) by 100.

Move the decimal: Another way to convert a quoted percentage to decimal format is to move the decimal two places to the left

6 0

3 years ago