Adding extra zeros to the right of the last decimal digit does not change the value of the decimal number (Math League, 2008, pg. 1).
Children should also be familiar with the whole number portion and with naming what digit is in what place. For instance, in 14.65, the whole number portion is 14. An example of the latter can be illustrated with 4.165. In this number, 4 is in the ones place, 1 is in the tenths place, 6 is in the hundredths place, and 5 is in the thousandths place (Math League, 2008, pg. 2).
A variety of specific examples or tasks can be used to check student understanding of rounding with decimals to the nearest tenth and to detect the existence of any possible conceptual and/or procedural errors. First of all, if the assignments are being conducted via paper and pencil, traditional assessment instruments such as the paper test can be used to measure success or detect weak areas. Second of all, if the assignments are being conducted via computer software drills, the software often gives immediate feedback that can be used to detect any strengths and weaknesses that students may have. Third, if the assignments are being conducted via flash cards, immediate feedback can be gained and recorded by quickly jotting the notes regarding the students performance in a notebook for later analysis and recommendations or guidance in the area (Reys, et.al., 2004).
How to Teach Rounding with Decimals to the Nearest Tenth
According to 321 Know (2008, pg. 2), "Rounding decimals is very similar to rounding other numbers. If the hundredths and thousandths places of a decimal is forty-nine or less, they are dropped and the tenths place does not change. For example, rounding 0.843 to the nearest tenth would give 0.8. If the hundredths and thousandths places are fifty or more, the tenths place is increased by one. The decimal 0.866 rounded to the nearest tenth is 0.9."
According to Math League (2008), the general rule for rounding decimal numbers must be understood first, and that rule is, "To round a decimal number to any decimal place value, we want to find the number with zeros in all of the lower places that is closest in value to the original number. As with whole numbers, we look at the digit to the right of the place we wish to round to. Note: When the digit 5, 6, 7, 8, or 9 appears in the ones place, round up; when the digit 0, 1, 2, 3, or 4 appears in the ones place, round down."
An example of rounding to the nearest tenth is:
In order to round the above number to the nearest tenth, we would first look at the number in the hundredths