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2 years ago

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An exam consists of 15 true-or-false questions. If a student guesses at every answer, what is the probability that he or she wil

l answer exactly 9 questions correctly? (Round your answer to three decimal places.).

1 answer:

Bas_tet [7]2 years ago

4 0

<span>C(15,9) * (1/2)^9 * (1/2)^6 = 5005/32768 = .153 approx</span>

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What is 629,462 rounded to the nearest hundred

WITCHER [35]

629,500 is the answer to your question

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3 years ago

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Aunty Joan packs a packet of sweets to Alice and Olivia. Alice and Olivia share sweets in the ratio 7:3. Alice gives 3 sweets to

aivan3 [116]

Initially, Alice had 28 sweets and Olivia 12 sweets.

Step-by-step explanation:

First assume that Aunty Joan has x number sweets.

Alice and Olivia shared the x sweets in a ration of 7:3, this means

Alice had 7/10 x sweets and Olivia had 3/10 sweets.

Alice gives 3 sweets to Olivia, Alice will remain with ;

$\frac{7}{10} x-3$

Then the new ratio changes to 5:3 which means Alice will have 5/8 x number of sweets.

Equate the number of sweets for Alice in the two cases, which is

$\frac{5}{8}x=\frac{7}{10} x-3\\ \\\frac{7}{10} x-\frac{5}{8} x=3\\$

$\frac{56x-50x}{80} =3\\\\\\\frac{6}{80} x=3\\\\\\6x=80*3\\\\\\x=240/6\\\\x=40$

So there were 40 sweets at first

Using the ratio of 7:3 then

Alice had 7/10 *40 = 28 sweets

Olivia had 3/10*40= 12 sweets

Alice gave Olivia 3 sweets, so she will remain with 28-3 =25 sweets. Olivia will now have 15 sweets.The new ratio will be 25:15 simplified as 5:3.

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Ratio : brainly.com/question/11095585

Keywords : Ratio

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3 years ago

If Angelica is 5 steps to the right of the classroom door and Brion is 12 steps to the left

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Angelica is 5 steps to the right while Brion is 12 steps to the left it is 17 steps because theyre going in the opposite directions :P

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3 years ago

Robin can run 1.71 kilometers in 10 minutes. How far can she run in 1.5 hours?

Flura [38]

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I think is 15.39 kilometers

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2 years ago

Need answers 1-8 equations and problems solving

djyliett [7]

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2) a. x = number of packages

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Add 33 to each side.

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