The mean of 10 terms is 3. If the first term | vedclass

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(B) Let the $10$ terms be $x_1, x_2, \dots, x_{10}$.Given that the mean is $\frac{\sum_{i=1}^{10} x_i}{10} = 3$,which implies $\sum_{i=1}^{10} x_i = 3

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$\frac{17}{2}$

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(B) Let the $10$ terms be $x_1, x_2, \dots, x_{10}$.Given that the mean is $\frac{\sum_{i=1}^{10} x_i}{10} = 3$,which implies $\sum_{i=1}^{10} x_i = 30$.When the first term is increased by $1$,the second by $2$,and the $i$-th term by $i$,the new sum of terms is:$\sum_{i=1}^{10} (x_i + i) = \sum_{i=1}^{10} x_i + \sum_{i=1}^{10} i$.Using the sum of the first $n$ natural numbers formula $\sum_{i=1}^{n} i = \frac{n(n+1)}{2}$,we get $\sum_{i=1}^{10} i = \frac{10 	imes 11}{2} = 55$.New sum $= 30 + 55 = 85$.The new mean is $\frac{85}{10} = \frac{17}{2}$.

The mean of $10$ terms is $3$. If the first term is increased by $1$,the second by $2$,and so on,then the new mean is:

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