In cell a15, you entered 567, and you should have entered 123. to correct this mistake, you should

You should click on the cell A15 and enter 123.

Explanation:

If you entered 567 in the cell A15 and you should have entered 123, to correct this mistake you can click on the cell A15 again and enter 123 which will eliminate the 567 that you had previously enter and 123 will appear in the cell.

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