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3 years ago

Of the 20 flash bulbs in a box, 2 are defective. an inspector will select 2 light bulbs simultaneously and at random from the bo

x. what is the probability that neither of the light bulbs selected will be defective

Mathematics

1 answer:

Shkiper50 [21]3 years ago

4 0

$|\Omega|=C(20,2)=\dfrac{20!}{2!18!}=\dfrac{19\cdot20}{2}=190\\
|A|=C(18,2)=\dfrac{18!}{2!16!}=\dfrac{17\cdot18}{2}=153\\\\
P(A)=\dfrac{153}{190}\approx81\%$

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3 years ago

Read 2 more answers

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Yakvenalex [24]

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3 years ago

A standard American Eskimo dog has a mean weight of 30 pounds with a standard deviation of 2 pounds. Assuming the weights of sta

nalin [4]

Answer:

Option 2 - Approximately 24–36 pounds

Step-by-step explanation:

Given : A standard American Eskimo dog has a mean weight of 30 pounds with a standard deviation of 2 pounds. Assuming the weights of standard Eskimo dogs are normally distributed.

To find : What range of weights would 99.7% of the dogs have?

Solution :

The range of 99.7% will lie between the mean ± 3 standard deviations.

We have given,

Mean weight of Eskimo dogs is $\mu=30$

Standard deviation of Eskimo dogs is $\sigma=2$

The range of weights would 99.7% of the dogs have,

$R=\mu\pm3\sigma$

$R=30\pm3(2)$

$R=30\pm6$

$R=30+6,30-6$

$R=36,24$

Therefore, The range is approximately, 24 - 36 pounds.

So, Option 2 is correct.

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3 years ago

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3 years ago

What is the voume of depth 1 2/3 inches and length of 2 1/3 inches and width 2 inches

Vlad [161]

Answer:

20/9 or 2 2/9 or 2.2 repeating

Step-by-step explanation:

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2 years ago