Work out the circumference of this circle.

Mathematics

1 answer:

Arada [10]3 years ago

6 0

Answer: 52.7856cm

Step-by-step explanation:

Circumference of a circle = 2πr

Note that radius = Diameter / 2 = 16.8/2 = 8.4cm

Circumference = 2πr

= 2 × 3.142 × 8.4

= 52.7856cm

Therefore, the circumference of the circle is 52.7856cm

You might be interested in

The mayor is interested in finding a 98% confidence interval for the mean number of pounds of trash per person per week that is

saul85 [17]

Solution :

Given :

Sample mean, $\overline X = 34.2$

Sample size, n = 129

Sample standard deviation, s = 8.2

a. Since the population standard deviation is unknown, therefore, we use the t-distribution.

b. Now for 95% confidence level,

α = 0.05, α/2 = 0.025

From the t tables, T.INV.2T(α, degree of freedom), we find the t value as

t =T.INV.2T(0.05, 128) = 2.34

Taking the positive value of t, we get

Confidence interval is ,

$\overline X \pm t \times \frac{s}{\sqrt n}$

$34.2 \pm 2.34 \times \frac{8.2}{\sqrt {129}}$

(32.52, 35.8)

95% confidence interval is (32.52, 35.8)

So with $95 \%$ confidence of the population of the mean number of the pounds per person per week is between 32.52 pounds and 35.8 pounds.

c. About $95 \%$ of confidence intervals which contains the true population of mean number of the pounds of the trash that is generated per person per week and about $5 \%$ that doe not contain the true population of mean number of the pounds of trashes generated by per person per week.