Rough division of numbers like 14 ÷ 3 gives ~4

Result: 4.3

Perform long division.

Move decimal in dividend same number of places as divisor.

Adjust decimals: 3.2 becomes 32, 13.76 becomes 137.6.

Multiplying numbers close to 5 and 5 gives ~25

Result: 23.40

Count total digits behind decimals in original numbers to place decimal in result.

Add partial products.

Calculate 52 x 45.

Estimated difference: ~30

Round numbers to nearest whole (e.g., 34.6 ≈ 35 and 4.864 ≈ 5).

Result: 29.736

Borrow as needed, subtract each column.

Align and add placeholder zeros.

Estimated sum: ~22

Round numbers to nearest whole (e.g., 18.4 ≈ 18 and 3.97 ≈ 4).

Result: 22.37

Add from right to left, carrying over as needed.

Align the numbers by decimal points.

Estimation Check:

Steps:

Key Technique: Make divisor a whole number by moving the decimal point.

Estimation Check:

Steps:

Key Technique: Ignore decimals initially, multiply as whole numbers.

Estimation Check:

Steps:

Use Placeholder Zeros to align numbers (e.g., 34.600).

Key Technique: Align decimals.

Estimation Check:

Steps:

Use Placeholder Zeros: Add zeros to make numbers appear more aligned (e.g., 18.4 becomes 18.40).

Key Technique: Line up the decimals in the numbers.

This refresher covers the basics to help reinforce understanding and accuracy in decimal operations.

For more detailed explanations, refer to additional videos linked in the video description.

Use estimation to validate answers.

Ensure decimals are correctly placed.

Example: 13.76 ÷ 3.2

Example: 5.2 x 4.5

Example: 34.6 - 4.864

Example: 18.4 + 3.97

Conclusion

Decimal Division

Decimal Multiplication

Decimal Subtraction

Decimal Addition

Overview

Math with Mr. J: Decimal Operations Review