We have a current rating average: $3.3/5$

Remove a rating of $4$. How do I find the new average?

Remove a rating of $4$. How do I find the new average?

Bairaxx
2022-10-25
Answered

We have a current rating average: $3.3/5$

Remove a rating of $4$. How do I find the new average?

Remove a rating of $4$. How do I find the new average?

You can still ask an expert for help

Liam Everett

Answered 2022-10-26
Author has **16** answers

If you know the number of observations, say it is $N$, then, if ${x}_{1},\dots {x}_{N}$ are the observations, you have that $\sum _{i=1}^{N}{x}_{i}=3.3N/5$. Therefore, the new average will be $\frac{3.3N/5-4}{N-1}$

If you don't know the number of observations, you can't find the new average. Your observations could be, for example, ${x}_{1}=4/5,{x}_{2}=2.6/5$ or ${x}_{1}=4/5,{x}_{2}=5.9/5,{x}_{3}=0$, and in the first case the new average is $2.6/5$, while in the second the new average is $2.95/5$.

If you don't know the number of observations, you can't find the new average. Your observations could be, for example, ${x}_{1}=4/5,{x}_{2}=2.6/5$ or ${x}_{1}=4/5,{x}_{2}=5.9/5,{x}_{3}=0$, and in the first case the new average is $2.6/5$, while in the second the new average is $2.95/5$.

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If the number of boys is $25$, then the number of girls is?

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