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3 years ago

14

the mean weight of 8 girls is 55kg and the mean weight of a group of boys if 52kg. the mean weight of all the students is 53.2kg

. how many boys are there?

1 answer:

Amanda [17]3 years ago

6 0

Add 55kg and 52 kg and 53.2 kg and divide by 8 and that will give you your answer

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$P(X=6)=\frac{e^{-4} 4^6}{6!}=0.1042$

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