Grade 5

Grade 5Decimals


Place Value in Decimals


Numbers are all around us, and they help us in many ways, especially in understanding quantities. Decimals, as numbers, allow us to deal with quantities that are not whole, allowing us to express values that are between whole numbers. For example, when we measure things like weight, height, or even money, we often need to use decimals to be precise. At the core of understanding decimals is the concept of place value. Let's dive deeper into this fascinating concept and understand how place value works with decimals.

What is local value?

Place value refers to the value of a digit based on its position or place in a number. The value of each position in a number is ten times the value of the position to its right. This is called the "base ten" system. It works like this:

    Thousand Hundred Ten One . Tenth Hundredth Thousandth 5 3 2 8 . 4 6 7
    Thousand Hundred Ten One . Tenth Hundredth Thousandth 5 3 2 8 . 4 6 7

In the above number, each digit has a different value according to its position:

  • 5 is in the thousands place, so it represents 5,000.
  • 3 is in the hundreds place, so it represents 300.
  • 2 is in the tenth place, so it represents 20.
  • The 8 is in the one place, so it represents 8.
  • 4 is in the tenths place, so it represents 0.4.
  • The 6 is in the hundredths place, so it represents 0.06.
  • 7 is in the thousandths place, so it represents 0.007.

The decimal point is important because it separates the whole number part from the fractional part.

Decimal point and its role

The decimal point is a point that separates whole numbers from fractional parts. In the number 52.647, the decimal point appears between 52 (the whole number) and 647 (the decimal fraction). When you see a decimal in a number, it tells you that the places beyond the decimal point are fractions of ten.

Visual example:

thousands Hundreds Tens people Tenth Hundred thousandth 5 2 7 1 , 6 4 3

Each column from the decimal point represents a power of ten, going up on the left and down on the right:

Dividing place values in decimals

Let us look more closely at each place value in a decimal number to understand what each one contributes to the overall number.

Whole number place value

  • Units place: It is located just before the decimal point. For the number 13.76, '3' is in the units place.
  • Tens place: It is the second place to the left of the decimal point. In 13.76, '1' is in the tens place which represents ten.

Decimal fraction place value

  • Decimal place: It is the first place just after the decimal point. Here the digit represents the tenths. In 13.76, '7' is in the tenths place which represents 0.7.
  • Hundredths place: The second place after the decimal point. It represents hundredths. In 13.76, '6' is in the hundredths place which represents 0.06.

Understand with more examples

Let us look at some examples to understand this concept better.

Example 1: Understanding 45.89

  • 45 is our whole number portion.
  • The 8 is in the tenths place, and means 8/10, or 0.8.
  • 9 is in the hundredths place, and means 9/100 or 0.09.
  • So, 45.89 gives us four tenths (40), five ones (5), eight-tenths (0.8), and nine-hundredths (0.09).
    45.89 = 40 + 5 + 0.8 + 0.09
    45.89 = 40 + 5 + 0.8 + 0.09

Example 2: Division of 2.345

  • 2 is in the ones place.
  • 3 is in the tenths place, representing 0.3.
  • The 4 is in the hundredths place, representing 0.04.
  • 5 is in the thousandths place, which represents 0.005.
  • When we add this up: 2.345 = 2 + 0.3 + 0.04 + 0.005.
    2.345 = 2 + 0.3 + 0.04 + 0.005
    2.345 = 2 + 0.3 + 0.04 + 0.005

Decimal place values extended beyond thousandths

Sometimes, decimals can extend beyond thousandths, including ten-thousandths, and so on. Let's look at an example of this.

Example 3: Understanding 0.6789

  • 6 is in the tenths place, which represents 0.6.
  • The 7 is in the hundredths place, which represents 0.07.
  • 8 is in the thousandths place, which represents 0.008.
  • 9 is in the ten thousandths place, representing 0.0009.
    0.6789 = 0.6 + 0.07 + 0.008 + 0.0009
    0.6789 = 0.6 + 0.07 + 0.008 + 0.0009

Playing with big numbers and decimals

As we understand the concept of decimal place values, it also helps us work with larger numbers. It is important to continue looking at numbers in terms of their place values as it not only aids understanding but also ensures accuracy in calculations.

Example 4: Breaking down large numbers: 1456.789

  • 1 is in the thousands place which represents 1000.
  • 4 is in the hundreds place which represents 400.
  • 5 is in the tenth place which represents 50.
  • 6 is in a position that represents 6.
  • 7 is in the tenths place which represents 0.7.
  • 8 is in the hundredths place which represents 0.08.
  • 9 is in the thousandths place which represents 0.009.
    1456.789 = 1000 + 400 + 50 + 6 + 0.7 + 0.08 + 0.009
    1456.789 = 1000 + 400 + 50 + 6 + 0.7 + 0.08 + 0.009

The important value of decimal places in life

Understanding decimal place values is helpful in many real-life scenarios. It's not just math - it's used in scientific measurements, financial transactions, cooking, and even when pricing and budgeting.

Example: Money and finance

Think about money. If you have $23.47, it means twenty-three dollars and forty-seven cents. Here, '47' are cents, which are parts of a dollar. Thus, decimal knowledge helps in many everyday activities.

Conclusion: Mastering decimals

Gaining an understanding of place values within decimals is an essential aspect of mathematics at every level of education. It helps develop an intuitive feel for numbers, and it enables us to communicate accurate information about the world around us. With practice, the concept of place value can become a reliable math tool for any situation involving decimals and beyond.

Keep practicing!

The best way to get really good at figuring out place value in decimals is to practice with different problems. Try breaking down the numbers the way we did here and before you know it, you'll be proficient at identifying and using decimal place values!


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