Addition and subtraction within 20 – Year 1 maths worksheet with answers to download as PDF

Look at the dots. Write the number sentence and the total.

Use the number line to work out each sum.

1. 7 + 5
2. 8 + 6
3. 9 + 3
4. 4 + 9
5. 6 + 7

Write the missing number in each number bond.

1. 6 + __ = 10
2. 3 + __ = 10
3. __ + 8 = 10
4. 10 − 4 = __
5. 10 − 9 = __

Cross out the counters. Write the number sentence and the answer.

Use the number line to subtract.

1. 15 − 3
2. 18 − 5
3. 13 − 6
4. 20 − 8
5. 11 − 9

Write the other three facts for each family.

1. 3 + 9 = 12
2. 8 + 5 = 13
3. 15 − 7 = 8

A baker makes 8 iced cakes and 7 jam cakes in the morning. During the day a customer buys 5 cakes.

1. How many cakes does the baker make in all?
2. Write the number sentence for part (a).
3. How many cakes are left after the customer buys 5?
4. The baker makes 4 more cakes in the afternoon. How many cakes are there now?

Tom has 9 red marbles and 6 blue marbles in a bag. He plays a game and loses 4 marbles.

1. How many marbles does Tom have at the start?
2. How many marbles does he have after the game?
3. He wins 3 marbles back. How many marbles now?
4. Does he have more or fewer marbles than at the start?

There are 12 ducks on a pond. 5 ducks fly away. Then 3 ducks swim in from the river.

1. How many ducks are on the pond after 5 fly away?
2. How many ducks are there after 3 more come?
3. Write both number sentences.
4. How many ducks were there at the start and how many are there at the end? Which number is bigger?

Mr Jones puts 11 books on the red shelf. He puts 8 books on the blue shelf. Some children borrow 6 books from the red shelf.

1. How many books are on the two shelves together?
2. How many books are left on the red shelf after the children borrow 6?
3. How many more books are on the blue shelf than the red shelf now?
4. Mr Jones adds 9 books to the red shelf. How many are on the red shelf now?

Priya has 13 football stickers. Her friend gives her 5 more. She gives 7 stickers to her brother. Her mum buys her a pack of 4 new stickers.

1. How many stickers does Priya have after her friend gives her 5 more?
2. How many does she have after giving 7 to her brother?
3. How many does she have after the new pack?
4. Is the end number bigger or smaller than 13? By how many?

A toy train has 6 red carriages and 9 green carriages. Zak takes 3 carriages off to put away. His sister has a train with 10 carriages.

1. How many carriages does Zak's train have to start with?
2. How many carriages does his train have now?
3. Whose train has more carriages now?
4. How many more carriages?

Family Singh pack a picnic. They take 9 sandwiches, 7 apples and 4 bananas. They also have a cake cut into 8 slices. They eat 5 apples and 6 sandwiches.

1. How many pieces of fruit (apples and bananas) are there?
2. How many sandwiches are left after they eat 6?
3. How many apples are left after they eat 5?
4. How many sandwiches and apples are left in total?

An ice cream van sells ice creams on a hot day. At lunchtime it sells 9 vanilla and 8 strawberry ice creams. In the afternoon it sells 6 more ice creams. The van started with 30 ice creams.

1. How many ice creams are sold at lunchtime?
2. How many are sold altogether, with the afternoon ones?
3. How many ice creams are left? Count back from 30 or take away.
4. The owner says "We sold fewer than 25 ice creams." Is she right?

A bus leaves the bus station with 14 people on board. At the first stop, 6 people get off and 3 people get on. At the second stop, 5 people get off and 8 people get on.

1. How many people are on the bus after 6 get off at the first stop?
2. How many are on the bus after the 3 people get on?
3. How many are on the bus after the second stop?
4. Is the bus fuller now or at the start? Explain.

Dani makes a game with number cards. She puts the cards 4, 5, 6, 7, 8, 9 on the table. She asks you to find pairs that make 13.

1. Which two cards add up to 13? Find as many pairs as you can.
2. Which two cards make the smallest total?
3. Which two cards make the biggest total?
4. Are there two cards that make exactly 10?

Ella marks her little brother's homework. Some of his answers are wrong. Check each one. If it is wrong, write the right answer.

1. 8 + 5 = 12
2. 14 − 6 = 8
3. 9 + 9 = 18
4. 15 − 7 = 7

Nina is getting party bags ready. She has 20 small toys. She puts 8 toys in the first bag and 7 toys in the second bag. She wants to put the rest in a third bag.

1. How many toys are in the first and second bags together?
2. How many toys are left for the third bag?
3. Write the sum for part (b) as a subtraction and check it with an addition.
4. Is the third bag fuller than the first bag? Explain.

Each shape hides a number. Work out the number.

1. A + 6 = 14. What is A?
2. 13 − B = 5. What is B?
3. C + C = 16. What is C?
4. 12 − D = D. What is D?

Zoe has five number cards: 2, 3, 4, 5 and 6. She wants to find pairs of cards that make a total of 9.

1. Which two numbers from the list add to 9? Find all the pairs.
2. Which number is not in any pair?
3. Which card goes with the 3 to make 9?
4. If the total is 11 instead, which pairs work?