The Brainliest Answer!
you can use auto sum in MS excel using following steps :-
     i. click on the cell which you want to autosum
     ii. click on the auto sum button  locatd in the corner of the MS excel window .
     iii. a dotted box appears which show that the range of the cells to be added appears with formula .
     iv. press ENTER 
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Use the SUM function to total numeric values in a common row or column

1. on a worksheet, click a cell below or to the right of the numeric values that you want to total.

2. on the hometab, in the editing group, click auto sum.

3. press ENTER to display the SUM function result in the selected cell.

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