Addition on a Number Line up to Twenty—Let's Practise!

Addition on a Number Line up to Twenty—Let's Practise! exercise

• What is 5 + 4?

  Hints

  Have a look at this number line to 10 to help you fill in the missing numbers.

  The arrows show 4 jumps from 5. Which number do we land on? That is the answer.

  Solution

  5 + 4 = 9

  The missing numbers were 6, 7, 8 and 9. When we count 4 jumps from 5, we get to 9.

• Can you use the number line to solve the problems?

  Hints

  Find the first number in the number sentence on the number line. Once you have done that, count forwards by the second number.

  For example, if we were solving 13 + 5, we would find 13 on the number line and then jump forwards 5 spaces.

  This picture of part of a number line shows how we would use the number line to solve 13 + 5.

  Solution

  The above picture of part of a number line shows how we would solve 12 + 6. We would start on 12 and jump 6 spaces forwards to land on 18. 12 + 6 = 18

  • 4 + 8 = 12
  • 11 + 8 = 19
  • 5 + 9 = 14

• Can you complete the number line and solve the problem?

  Hints

  We are counting on 3 from 12, so there are three gaps to fill in on the number line. What numbers come after 12?

  Once you have filled in the gaps, make three jumps from 12. Which number do you land on?

  Have a look at this number line from 11 to 20 to help you complete the above number line.

  Solution

  12 + 3 = 15

  The missing numbers were 13, 14 and 15.

  When we make 3 jumps forwards from 12, we land on 15.

• Use the number line to solve the problems.

  Hints

  Find the number you are starting with on the number line, then jump forwards by the other number.

  For example, when you are solving 13 + 5, find 13 on the number line and then jump 5 spaces forwards.

  When you are solving 4 + 4 + 2, start on 4 and jump 4 spaces forwards, then jump 2 more spaces forwards.

  Solution

  13 + 5 = 18. Start on 13 and jump 5 spaces forwards as shown above. You will land on 18.

  7 + 6 = 13

  9 + 7 = 16

  4 + 4 + 2 = 10

• Can you solve 4 + 3?

  Hints

  We are adding onto 4, so the answer has to be greater than 4.

  Use the jumps on the number line to help you. Where do they end?

  Solution

  4 + 3 = 7

• Beth's Walk.

  Hints

  Look carefully at the numbers in each sentence. Can you make a number sentence?

  Can you use or draw your own number line to help you?

  Here is a number line to help you.

  Solution

  One day, Beth went for a walk. As she was walking she saw 4 blue cars and 6 red cars. Altogether, that is 10 cars. 4 + 6 = 10

  Beth was walking her 2 dogs. She also saw 7 more dogs on her walk. Altogether, that is 9 dogs. 2 + 7 = 9

  Beth walked past some shops. There were 8 shops on one side of the road and 7 shops on the other side. Altogether, that is 15 shops. 8 + 7 = 15

  Beth also walked past 1 apple tree, 5 horse chestnut trees and 3 oak trees. Altogether, that is 9 trees. 1 + 5 + 3 = 9