Please help! I’m bad at fractions

The circumference of a circle is 106.76 meters. What is the circle's diameter?

Flura [38]

C = 2*pi*r
So, C = pi*d
106.76 = pi*d
106.76/pi = d
d = ~33.98

5 0

3 years ago

The shape of the distribution of the time required to get an oil change at a 15-minute oil-change facility is unknown. However,

horsena [70]

Answer:

The mean oil-change time that would there be a 10% chance of being at or below is 15.46 minutes.

Step-by-step explanation:

We are given that records indicate that the mean time is 16.2 minutes, and the standard deviation is 3.4 minutes.

On a typical Saturday, the oil-change facility will perform 35 oil changes between 10 A.M. and 12 P.M. Assuming that data follows normal distribution.

Let $\bar X$ = sample mean time

The z score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean time = 16.2 minutes

$\sigma$ = standard deviation = 3.4 minutes

n = sample size = 35 oil changes

Now, the mean oil-change time that would there be a 10% chance of being at or below is given by;

P(X $\leq$ x) = 0.10 {where x is required mean oil-change time}

P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ $\leq$ $\frac{x-16.2}{\frac{3.4}{\sqrt{35} } }$ ) = 0.10

P(Z $\leq$ $\frac{x-16.2}{\frac{3.4}{\sqrt{35} } }$ ) = 0.10

Now, in the z table the critical value of X which represents the below 10% of the probability area is given as -1.282, that means;

$\frac{x-16.2}{\frac{3.4}{\sqrt{35} } }$ = -1.282

x - 16.2 = $-1.282 \times {\frac{3.4}{\sqrt{35} } }$

x = 16.2 - 0.74 = 15.46 minutes

Hence, the mean oil-change time that would there be a 10% chance of being at or below is 15.46 minutes.

8 0

3 years ago

Estimate the value of 9.9²x1.79

Darina [25.2K]

Answer: Not necessarily an estimate but your answer should be 175.4379 in decimal form.

3 0

4 years ago

Which of these sentences are propositions?

ExtremeBDS [4]

Answer:

a) True

b) False

c) True

d) False

e) Not a proposition

f) Not a proposition

Step-by-step explanation:

Proposition:

It is a declarative statement that is either false or true.
It cannot be both true or false.

a) Boston is the capital of Massachusetts.

The given statement is true. Hence, the given statement is a proposition.

b) Miami is the capital of Florida.

The given statement is false. Hence, the given statement is a proposition.

c) 2 + 3 = 5.

The given statement is true. Hence, the given statement is a proposition.

d) 5 + 7 = 10.

The given statement is false. Hence, the given statement is a proposition.

e) x + 2 = 11.

The given statement can neither be true or false. It depends on the value of x. Hence, it is not a proposition.

f ) Answer this question.

The given statement is not a declarative in nature. Hence, it is not a proposition.

4 0

3 years ago

Write an expression to model the following situation: Lisa and Tom are baking cookies for the annual bake sale. Lisa has baked 6

zimovet [89]

The answer is 66+126=Cookies

3 0

3 years ago