The mean and standard deviation of 100 observations were calculated as 40 and 5.1, respectively by a student who took by mistake 50 instead of 40 for one observation. What are the correct mean and standard deviation?

Explanation

`barx=1/n sum_(i=1)^nx_i`


`=>sumx_i=nbarx`


`=100xx40`


`=4000`


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