Rounding decimals helps to make calculation easier.

If this quiz gives you difficulty, refer to the quizzes on place values.

Rounding numbers to the nearest tenth is as follows.

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Answer all questions carefully. You have three chances at this quiz.

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**What are compatible numbers?**Compatible numbers are numbers that are easy to compute using the four basic operations: addition, subtraction, multiplication, or division. Compatible numbers help you do mental math. It involving rounding numbers to the nearest tens, hundreds, thousands, or ten thousand. For this reason it helps in solve estimating questions.

**Example**:

Find the sum of 512 and 419.

To solve this we must first round the numbers to the nearest tens or hundreds. In this example we round it up to the nearest tens.

Let do some questions using the four basic operations.

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Answer all questions.

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Answer all following questions. You have

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Answer the following questions.

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Exercise to create number patterns.

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Pattern

Answer the following questions.

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This quiz is timed and is limited to 5 trials. Answer all the questions before you submit.

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This exercise will focus on rounding off whole number to the nearest ten, hundred, and thousand. View the videos before you start the exercise.

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Practice exercise.

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Even though the numeral **4 457** is a large number, it can be read as:

4 000 and 400 and 50 and 7.

4 000 + 400 + 7

The expanded form for the number** 4 457** can also look like this:

(4 x 1000) + (4 x 100) + (5 x 10) + (7)

Note:

There is a difference between the value of a digit and the amount of say hundreds or tens or even ones in a number.

For example: How many hundreds are there in the numeral 2307?

Observe that the question states hundreds. So there are 23 hundreds in the numeral 2307.

Time for some questions:

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Answer all the questions.

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Answer all the questions.

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Answer all the questions.

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Practice

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Review

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Consolidate

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Quiz is testing expanded form, place value, addition and subtraction.

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Our numeration system is based on the decimal system or base 10. You have learnt that the place value of the digits in any numeral in base 10 increases 10 times from right to left, and decreases 10 times from left to right.

So:

Numeral: 24 = (2 x 10) + (4 x 1)

Numeral: 524 = (2 x 100) + (2 x 10) + (4 x 1)

Separating digits in this manner is called expanded notation.

Consider:

28,472 = (2 x 10,000) + (8 x 1,000) + (4 x 100) + (7 x 10) + (2 x 1)

23472 = 20,000 + 8,000 + 400 + 70 + 2

Practice:

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Consolidation

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Review.

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