Kevin ran 6.8 miles yesterday and 10.4 miles presently. How many more miles did he run today?
To ?nd out how many more miles he ran today, subtract yesterday's miles from today's miles. 10.4 - 6.8. To subtract decimals, line the numbers up vertically so in which the decimal points align. Then, subtract generally. If you chose b, you made an error in borrowing. You forgot to modify the 10 to a 9 while borrowing 1 for the 4.