# Maths – Rebalancing when adding 9 and 11

This week in maths Year 2 have been learning to rebalance number sentences in order to make them easier to work out.

First we learnt about rebalancing when adding 9. We used tens frames and counters to help us.

To solve 9 + 6 first we made each number on a tens frame using counters.

Then we rebalanced the number sentence by taking one counter from the 6 and giving it to the 9. Now our number sentence is 10 + 5

.

10 + 5 is much easier to solve than 9 + 6.

We wrote down 9 + 6 = 10 + 5 = 15

Then we used what we knew to apply the same strategy when adding 11.

To solve 11 + 6 first we made each number on a tens frame using counters.

Then we rebalanced the number sentence by taking one counter from the 11 and giving it to the 6. Now our number sentence is 10 + 7.

10 + 7 is much easier to solve than 11 + 6.

We wrote down 11 + 6 = 10 + 7 = 17

Have a look at some of our hard work.

How to help at home

• Make your own tens frames at home and use lego bricks or similar as counters.
• Use your own tens frame to solve some calculations where you need to add 9 or 11.
• Pick 2 numbers below 20 to add together. Challenge your family to add them together as well. Ask everyone to epxlain how they worked out the answer. Did you all use the same strategies?
• Play board games with 2 dice to practise adding the amounts together mentally.
• Keep playing Numbots.