# Lesson Two

Terrific Tuesday folks!

STARTER:

1. Ask someone to give you a two digit number.  Or pick to cards to make a two digit number. e.g.  49
2. Now tell them how many tens are in the number.  e.g. There are four tens.
3. Now what is the value of the ten.  e.g. 40
4. Now tell me ten more and ten less e.g.  59 and 39.
5. repeat a few times.

So today we are going to recap the INVERSE operation.   Remember INVERSE means the opposite action.  So if you have subtracted you will add to check your answer.

e.g.     45 - 25 =   (if you need to draw out your problem, see pictures below)

Once you have your answer you will do the inverse which in this case is to add.  So you will add your answer to the last number in the number sentence. See pictures below.

Now have a go at finding the inverse of these subtraction problems.

Write a word problem for one of the problems above.  Can you now write an inverse word problem?

e.g.   Mrs R-J had 13 bananas.  Mrs Edwards ate 6 of them!  How many bananas has Mrs R-J got left?

13 - 6 = ?

The inverse word problem would be .....

Mrs R-J had seven bananas.  Mrs Edwards gave her six more bananas.  How many bananas does Mrs R-J have now?

7 + 6 = 13

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