Grade 8Math

Place Value

Place value in decimals works by assigning each digit a value based on its position relative to the decimal point, with each place being one tenth of the place to its left. The first decimal place is tenths (1/10), the second is hundredths (1/100), the third is thousandths (1/1000), and so on. The decimal 0.125 equals 125/1000 because the last digit is in the thousandths place. This Grade 8 math skill from Yoshiwara Core Math Chapter 2 solidifies decimal understanding needed for all decimal arithmetic, percent calculations, and scientific notation. Understanding place value is foundational for reading measurements, interpreting data, and understanding the structure of our number system.

Key Concepts

Property The place value of the last digit tells us the denominator of the fraction. Each decimal place is one tenth of the preceding place. For example, the places after the decimal point are tenths, hundredths, thousandths, and so on.

Examples The decimal $0.6$ is read as six tenths and is written as the fraction $\frac{6}{10}$. The decimal $0.09$ is read as nine hundredths because the last digit, 9, is in the hundredths place. It is written as $\frac{9}{100}$. The decimal $0.125$ is read as one hundred twenty five thousandths and is written as $\frac{125}{1000}$.

Explanation Think of place value as a digit's address. The further right it is from the decimal point, the smaller its value. Each spot is ten times smaller than the one to its left, just like a penny is worth less than a dime.

Common Questions

What is place value in decimals?

In decimal numbers, each digit has a value determined by its position. Moving right from the decimal point: tenths (0.1), hundredths (0.01), thousandths (0.001), etc. Each place is 10 times smaller than the place to its left.

How do you read a decimal number using place value?

Identify the decimal place of the last digit. That determines the denominator of the fraction. For example, 0.6 is six tenths, 0.09 is nine hundredths, and 0.125 is one hundred twenty-five thousandths.

How do you convert a decimal to a fraction using place value?

The digits after the decimal point form the numerator, and the denominator is the place value of the last digit as a power of ten. For example, 0.07 = 7/100 (hundredths place), and 0.008 = 8/1000 (thousandths place).

When do 8th graders learn about decimal place value?

Students study decimal place value in Grade 8 math as part of Chapter 2 of Yoshiwara Core Math, which covers numbers and variables including decimal concepts.

How does place value help with rounding?

Understanding place value is essential for rounding. To round to the nearest hundredth, you look at the thousandths digit. Knowing which position each digit occupies makes rounding rules clear and systematic.

What is the place value of each digit in 3.741?

In 3.741: 3 is in the ones place, 7 is in the tenths place (0.7), 4 is in the hundredths place (0.04), and 1 is in the thousandths place (0.001). The value is 3 + 0.7 + 0.04 + 0.001 = 3.741.