Easy📚 Decimals

Adding Decimals Step by Step

Grades 5-6Key Stage 2Årskurs 4-5

Problem

Add: 12.45 + 3.8

📝Step-by-Step Solution

Write the numbers vertically

Stack the numbers on top of each other, making sure to line up the decimal points.

12.45 + 3.80

Add placeholder zeros

Add zeros to make the decimal parts the same length: 3.8 becomes 3.80. This doesn't change the value.

3.8 = 3.80

Add from right to left

Hundredths: 5 + 0 = 5. Tenths: 4 + 8 = 12 (write 2, carry 1). Ones: 2 + 3 + 1 = 6. Tens: 1 + 0 = 1.

Bring down the decimal point

The decimal point in the answer goes directly below the decimal points above.

12.45 + 3.80 = 16.25

✅Final Answer

16.25

The key to adding decimals is alignment! Always line up the decimal points, then add as you would with whole numbers. Adding zeros as placeholders helps keep columns aligned. The decimal point in your answer goes straight down.

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This worked example is part of the broader decimals guide. Review the method, practice related skills, and create a printable assessment when you are ready.

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