Explanation of Rounding
Look at this number: 23. This is a whole number. It means 23 whole objects. It might mean 23 students, 23 candy bars, 23 days of the week, 23 dogs
Now, look at this number: 23.9 This is a whole number and a decimal. The whole number part is 23. The .9 is the decimal. You can have 23.9 candy bars. You can have 23.9 days of the week. You cannot have 23.9 students and you cannot have 23.9 dogs.
If you have 23.9 candy bars, you almost have 24 candy bars. That is why 23.9 is rounded to 24.
If you are asked to round to the NEAREST WHOLE NUMBER, you must look to the number to the right......in the tenths place.
164.2
What is the whole number?_______________ What number is in the tenths place? ________
Is the number 2 large enough to change 164 to 165? __________
What whole number would 164.2 be rounded to? _____________
Let’s look at another number: 349.672
What is the whole number? __________
What is the decimal? __________
What number is in the tenths place? ___________
What number is in the hundredths place? ____________
Round 349.672 to the nearest whole number. _____________
If you are asked to round 349.672 to the nearest TENTH, you must look to the number to the right.... in the hundredths place.
What number is in the tenths place? _________
What number is in the hundredths place? __________
Is the 7 large enough to change the .6 to a .7? ____________
What tenth would 349.672 be rounded to? _____________
If you are asked to round 349.672 to the nearest HUNDREDTH, you must look to the number to
the right....in the thousandths place.
What number is in the hundredths place? _________
What number is in the thousandths place? ____________
Is the 2 large enough to change the 7 to an 8? ___________
What hundredth would 349.672 be rounded to? __________________
Round these numbers to the nearest whole number:
34.2 _________ 1,768.9 ________ 456.48 _______
8.4 ________ 19,056.1 ___________
Round these numbers to the nearest tenth:
34.26________ 1768.94 _________ 456.48 _______
8.45 _______ 19,056.12 ________
Round these numbers to the nearest hundredth:
34.267 ________ 1768.942 ________ 456.485 ________
8.459 _______ 19056.123 ________
© Ellen Gabor, 1998