Kendra and her horse completed the barrel racing course in 15.839 seconds. what is this number rounded to the nearest tenth? : explain how you decided

15.839 rounded to the nearest tenth would be 15.8. It would be that because when you look at the number to the right when it is below five you leave the number your rounding alone, but when the number to the right is higher you would add one to the number that you are rounding. Easy. 

The answer is 15.84.

To find the nearest tenth, you go to the 3rd place after the decimal and decide: if the value is 5 or greater, go to the second place after the decimal and round up one. If it does not, the value of the second decimal stays the same.