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2 years ago

The area of a circle is 42.29m2. Find the length of the diameter rounded to 1 DP.

Mathematics

1 answer:

Firdavs [7]2 years ago

6 0

Step-by-step explanation:

area of a circle=πr²

=42.29m²

42.29m²=πr²

then find for r, multiply it by two to obtain the diameter of the circle

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The University of Washington claims that it graduates 85% of its basketball players. An NCAA investigation about the graduation

Nonamiya [84]

Probabilities are used to determine the chances of events

The given parameters are:

Sample size: n = 20
Proportion: p = 85%

<h3>(a) What is the probability that 11 out of the 20 would graduate? </h3>

Using the binomial probability formula, we have:

$P(X = x) = ^nC_x p^x(1 - p)^{n -x}$

So, the equation becomes

$P(x = 11) = ^{20}C_{11} \times (85\%)^{11} \times (1 - 85\%)^{20 -11}$

This gives

$P(x = 11) = 167960 \times (0.85)^{11} \times 0.15^{9}$

$P(x = 11) = 0.0011$

Express as percentage

$P(x = 11) = 0.11\%$

Hence, the probability that 11 out of the 20 would graduate is 0.11%

<h3>(b) To what extent do you think the university’s claim is true?</h3>

The probability 0.11% is less than 50%.

Hence, the extent that the university’s claim is true is very low

<h3>(c) What is the probability that all 20 would graduate? </h3>

Using the binomial probability formula, we have:

$P(X = x) = ^nC_x p^x(1 - p)^{n -x}$

So, the equation becomes

$P(x = 20) = ^{20}C_{20} \times (85\%)^{20} \times (1 - 85\%)^{20 -20}$

This gives

$P(x = 20) = 1 \times (0.85)^{20} \times (0.15\%)^0$

$P(x = 20) = 0.0388$

Express as percentage

$P(x = 20) = 3.88\%$

Hence, the probability that all 20 would graduate is 3.88%

<h3>(d) The mean and the standard deviation</h3>

The mean is calculated as:

$\mu = np$

So, we have:

$\mu = 20 \times 85\%$

$\mu = 17$

The standard deviation is calculated as:

$\sigma = np(1 - p)$

So, we have:

$\sigma = 20 \times 85\% \times (1 - 85\%)$

$\sigma = 20 \times 0.85 \times 0.15$

$\sigma = 2.55$

Hence, the mean and the standard deviation are 17 and 2.55, respectively.

Read more about probabilities at:

brainly.com/question/15246027

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2 years ago

How many Hostel rooms have 11 or fewer guest

I am Lyosha [343]

I think the answer is 20

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2 years ago

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What is Y/-3 = 1/6,

telo118 [61]

Answer: y=1/2 of the whole

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Benito rune 1/10 of a mile each day. Which shows how to find the number of days it will take for Benito to run 3/5 of a mile

juin [17]

It'll take him 6 days to run 3/5 of a mile....

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2 years ago

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Can you help me with this problem please

Over [174]

Remark

I think you want us to do both 3 and 4

Three

QR is 4 points going left from the y axis + 2 points going right from the y axis.

QR = 6 units long.

RT is 4 units above the x axis and 3 units below the x axis

RT = 7 units long

TS = 3 units. For this one you just go from T to S. The graph really helps you. You just need to count.

Problem 4

You need to find the area of the combined figure. You could do it as a trapezoid, which might be the easiest way. I'll do that first.

Area = (b1 + b2)*h/2

Givens

B1 = QR = 6

B2 = UT + TS = 6 + 3 = 9

h = RT = 7

Area

Area = (6 + 9)*7/2

Area = 15 * 7 / 2

Area = 52.5

Comment

You could break this up into a rectangle + a triangle

Find the area of QRTU and add the Area of triangle RTS

<em>Area of the rectangle </em>= L * W

L = RT = 7

W = QR = 6

Area = 7 *6 = 42

<em>Area of the triangle</em> = 1/2 * B * H

B = TS = 3

H = RT =7

Area = 1/2 * 3 * 7

Area = 1/2 * 21

Area = 10.5

Total Area = 42 + 10.5 = 52.5 Both answers agree.

3 0

2 years ago