Mini Minds Hub · Free printable
Adding Decimals: Free Printable Worksheet for Year 5
- ForYear 5
- StageKey Stage 2
- CostFree
- FormatPrintable PDF
Adding Decimals is a free printable maths worksheet for Year 5 (ages 9 to 10). Children add decimals with one or two decimal places by lining up the decimal points. It needs only a pencil, takes about 10 to 15 minutes, and page 2 gives the grown up notes, help ideas, a stretch task and the answers.
It comes from the Mini Minds Hub, the free library of printables from Jaques of London, the British games and toy company that has been making games for families since 1795. Print both pages, give page 1 to your child and keep page 2 for yourself. Black and white printing works well.
What is on the sheet
Children work through numbered questions, each one an addition of two decimals, with space to write the answer. The sums start with decimals that have the same number of places, then move on to pairs with different numbers of places, and some cross a whole number. The main job is to write each sum in columns with the decimal points lined up.
- 2.5 + 1.3
- 4.6 + 3.7
- 0.7 + 0.5
- 12.4 + 5.3
- 3.25 + 1.5
- 6.8 + 2.35
- 0.9 + 0.09
- 7.5 + 2.5
A worked example
4.7 + 2.36
This question is not on the sheet. It shows two ways to work, and both give the same answer.
Method 1: column method- Write 4.7 as 4.70 so both numbers have two decimal places.
- Line up the decimal points. Put 4.70 above 2.36.
- Add the hundredths: 0 + 6 = 6.
- Add the tenths: 7 + 3 = 10 tenths. Write 0 and carry 1 to the ones.
- Add the ones: 4 + 2 + 1 = 7. Put the decimal point straight down in the answer.
- Split 4.7 into 4 and 0.7. Split 2.36 into 2, 0.3 and 0.06.
- Add the ones: 4 + 2 = 6.
- Add the tenths: 0.7 + 0.3 = 1.
- Add the hundredths: 0.06.
- Put the parts together: 6 + 1 + 0.06 = 7.06.
Why line up the decimal point?
A decimal is a way of writing a part of a whole using place value. The digits to the right of the decimal point are tenths, then hundredths. When we add, we can only combine amounts of the same size. Lining up the decimal points puts tenths under tenths and hundredths under hundredths, so each column adds like with like.
Many mistakes come from lining up the right hand edges of the numbers instead. That works for whole numbers but not for decimals. Writing a zero in an empty place, such as 1.5 as 1.50, does not change the value. It simply fills the gap, so the columns are easy to see and nothing gets missed.
Decimals around us
- Decimal means based on ten. Each place is ten times bigger than the place to its right.
- Money uses decimals. In pounds and pence, the point separates whole pounds from parts of a pound.
- Rulers use decimals too. A centimetre is divided into ten millimetres, so lengths such as 4.5 cm are common.
- Ten tenths make one whole. That is why tenths sometimes carry into the ones column.
- Shop scales often show weight in kilograms with a decimal point.
Skills and curriculum link
- Adding decimals
- Place value
- Lining up columns
- Carrying across the point
- Checking by estimating
Ideas that help with decimals
- Same place, same columnTenths go under tenths and hundredths under hundredths. The decimal points should sit in a straight line, one above the other.
- Zeros as placeholdersAdding a zero at the end of a decimal does not change its value. It can make a column sum easier to read.
- Ten tenths make oneIf a column adds to ten or more, carry to the next column on the left, even when the column is on the other side of the point.
- Estimate firstRound each number to the nearest whole number and add. Use that rough answer to check if the real answer is sensible.
Key words
- Decimal pointThe dot that separates whole numbers from parts of a whole.
- TenthOne of ten equal parts of a whole. It is the first place after the decimal point.
- HundredthOne of one hundred equal parts of a whole. It is the second place after the decimal point.
- Place valueThe value a digit has because of where it sits in a number.
- Placeholder zeroA zero written in an empty place so the columns line up. It does not change the value.
- CarryMove ten of one place into one of the next place to the left.
How to use it
- Print both pages. Page 1 is for your child. Keep page 2, which has the notes and answers.
- Give your child squared paper. Show them how to write one digit in each square, with the decimal points in one line.
- Do the first question together. Ask them to say which column each digit sits in.
- Let them try the rest alone. Check using page 2 and ask, "How did you work that out?"
- Come back another day and redo any that felt tricky. Repeating a familiar sheet builds confidence.
Help, stretch and game ideas
If it feels too hard
Write each sum in a column on squared paper, one digit per square. Draw the decimal point in the same place in both numbers and in the answer. Add zeros in empty places, such as 1.50, so no column is left blank.
To stretch confident children
Write three different decimal additions that total exactly 10. Then swap with a friend and check each other's. Try to make one with tenths only, and one with hundredths in it.
Make it a game
Roll a dice twice and write the digits as a decimal, such as 3.4. Do it again to make a second decimal, then add them. The player with the larger total wins the round. Play five rounds.
Mistakes to watch for
Watch forA child lines up the right hand edges of the numbers, so tenths sit under hundredths.
Try thisDraw a vertical line through the decimal points on squared paper. Say the place names aloud as you add each column.
Watch forA child forgets to write the decimal point in the answer, or puts it in the wrong place.
Try thisPut the point in the answer first, straight below the points in the question. Then add the digits.
Watch forA child ignores a carry, especially when it moves from the tenths into the ones.
Try thisWrite a small carry digit under the next column. Remind them that ten tenths make one whole.
Talk about it
- Why do we line up the decimal points before adding?
- What does the 5 mean in 3.25? What does it mean in 3.52?
- When might you need to carry in a decimal sum?
- How could you estimate the answer before you start?
- Where have you seen decimals outside school?
- Is writing 1.5 as 1.50 a different number or the same? How do you know?
Take it off the page
Pretend shop
Make price labels for toys or books with pounds and pence. Pick two items, add the prices on paper and check with pretend coins.
Measure and add
Use a ruler or tape measure to measure two objects in centimetres, with halves or tenths. Add the lengths and say the total.
Place value cards
Make cards for digits 0 to 9 and a decimal point card. Build two decimals, line them up on the table and add them.
Who it is for
Parents
Sit beside your child for the first question, then let them lead. Squared paper helps a great deal. Keep sessions to 10 or 15 minutes, and praise careful lining up as much as correct answers.
Teachers
Use it as a starter, plenary, homework task or early finisher activity. It practises addition with decimals and place value, and page 2 gives support and stretch ideas for mixed ability groups. It needs no preparation beyond printing.
Home educators
Pair it with everyday decimals such as prices, lengths and weights. It works on its own or as part of a wider maths plan, and you can print it again for brothers, sisters or revision a few weeks later.
Where this fits
Before this, children learn the place value of tenths and hundredths and how to add whole numbers in columns. They also meet decimals on number lines and in money and measures.
After this, children can move on to subtracting decimals, adding numbers with more decimal places and solving problems with money and measures. The same idea of keeping like places together carries through all of it.
Questions parents and teachers ask
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Preview the full PDF
Made by Jaques of London, making games for families since 1795. A printable supports classroom learning and does not replace a teacher.