How do you get 876 nearest 10 and show the way?

To round the number:

1. Find the required digit, noting the number upto it
2. Look at the next digit to its right. if it is 5 or more, add one to the required digit (carrying as necessary to the digits to its left) otherwise if it is less than 5, leave it alone.
3. Replace all digits to the right of the required digit by 0s.

For 876:

1. 10s digit is 7 (number so far is 87...)
2. Next digit is 6 which is 5 or more, so add 1 to the 10s digit: 7 + 1 = 8 (no carry required)
3. Replace all digits to right of 10s by 0s: 880

876 to nearest 10 is 880.