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3 years ago

99 students choose to attend one of three after school activities: football, tennis or running.

Mathematics

1 answer:

nordsb [41]3 years ago

3 0

Answer: $\dfrac{49}{99}$

<u>Step-by-step explanation:</u>

There are 61 boys --> 38 girls

A) 19 chose football: 5 are girls --> 14 are boys

B) 38 girls: 28 chose running, 5 chose football --> 5 girls chose tennis

C) 31 students chose tennis: 5 are girls --> 26 are boys.

D) 61 boys: 14 chose football, 26 chose tennis --> 21 boys chose running.

$\large\boxed{\begin{array}{l|cc||c}&\underline{Boys}&\underline{Girls}&\underline{Total}\\Football&14&5&19\\Tennis&26&5&31\\\underline{Running}&\underline{\quad 21\quad}&\underline{\quad 28\quad}&\underline{\quad 29\quad}\\Total&61&38&99\end{array}}$

Total running = 21 boys + 28 girls = 49

Total students = 99

$\dfrac{\text{Total running}}{\text{Total students}}=\large\boxed{\dfrac{49}{99}}$

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3 years ago

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Step-by-step explanation:

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Compute the mean of this sample as follows:

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Compute the standard deviation of this sample as follows:

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4 years ago

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Answer:

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Step-by-step explanation:

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