Rounding Numbers

Question

51.57 dm (rounded off to nearest tenth of a dm)

Answer 1

To round to the nearest tenth, look to the right of the number in the tenth place. If it is "5 or more. let it soar"....if it is "4 or less, let it rest"

The number to the right of the 5 in the tenths place is 7, so the 5 will soar to 6 and everything to the right of the tenths place will be 0.

Therefore, 51.57 = 51.6 

Answer 2

Well, Samantha, hopefully you know how to round in general. The places after the decimal are opposite of before the decimal. If I go left, I have ones, tens, hundreds, etc.

 

The only difference is there are no oneths, so after the decimal goes tenths, hundredths, thousandths, etc.

 

Now, if I asked you to round to the nerest ten, you'd know that the 1 after the 5 is less than 5, so the 5 stays and we have 50.

 

Let's do tenths. That's the first digit after the decimal. The 7 after it is ≥ 5, so the 5 in the tenths place changes to a 6 and we have 51.6. There is no need to say 51.60 because 51.6 = 51.60, so we don't need the redundant 0.