Activity 11: Adding, Subtracting and Rounding Decimals

Front

What is rounding?

Back

Rounding is the process of adjusting a number to make it simpler and easier to work with, while keeping its value close to what it was. For example, rounding 4.5 to the nearest whole number gives 5.

Front

How do you round a decimal to the nearest tenth?

Back

To round a decimal to the nearest tenth, look at the hundredths place. If it's 5 or more, round up; if it's less than 5, round down.

Front

What is the sum of 10.9 and 8.6?

Back

The sum of 10.9 and 8.6 is 19.5.

Front

What is the sum of 10.9, 8.6, and 12.4?

Back

The sum is 31.9 hours.

Front

How do you subtract decimals?

Back

To subtract decimals, align the numbers by the decimal point and subtract as you would with whole numbers, placing the decimal point in the answer.

Front

What is 16.06 - 10.1?

Back

16.06 - 10.1 = 5.96.

Front

What is 2.98 + 5.3?

Back

2.98 + 5.3 = 8.28.

Front

What does it mean to round to the nearest whole number?

Back

Rounding to the nearest whole number means adjusting a decimal to the closest whole number. For example, 12.51 rounds to 13.

Front

Which number rounds to 12 when rounded to the nearest whole number?

Back

11.56 rounds to 12.

Front

What is the difference between addition and subtraction of decimals?

Back

Addition combines numbers to find a total, while subtraction finds the difference between numbers.