1. Mixed Addition & Subtraction L.O. TO BE ABLE TO WORK OUT MIXED ADDITION AND SUBTRACTION EXPRESSIONS Collect Homework

2. What must you remember?  You must remember that it is the sign IN FRONT of the number that tells you what to do with that number!  If the sign is plus you must add that number to the rest  If the sign is minus you must take that number away from the rest

3. You can add and take away in ANY ORDER  Example 138 + 76 – 94 To 138 we must add 76 and take away 94 I can add 76 first then take away 94 138 + 76 = 214 214 – 94 = 120 I can take away 94 first then add 76 138 – 94 = 44 44 + 76 = 120 FIRST NUMBER We can do the operations in any order but we MUST START WITH THE FIRST NUMBER !!!

4. Example: 42 – 70 + 51 - 3  We must start with 42 but we can add and take away in any order  Notice that we can’t take away 70 first so we must choose a different order here! I can add 51 then take away 3 and 70 42 + 51 = 93 93 – 3 = 90 90 – 70 = 20 I can take away 3 first then add 51 and take away 70 42 - 3 = 39 39 + 51 = 90 90 – 70 = 20

5. Example: 95 – 161 + 75 +10  We must start with 95 but we can add and take away in any order  Notice that we can’t take away 161 first so we must choose a different order! I can add 75 first then take away 161 and add 10 95 + 75 = 170 170 – 161 = 9 9 + 10 = 19 I can add 10 first then 75 then take away 161 95 + 10 = 105 105 + 75 = 180 180 – 161 = 19

6. Mixed addition & subtraction sums  You MUST ALWAYS start with the FIRST number  To this first number you can then add or take away in any order  The sign IN FRONT of the number tells you what to do with that number

7. Suggestion..  If you can work the sum in the order that it is given, then do it !  If you can’t, then remember that the sign in front tells you what to do with the number!

8. Bingo Activity Time 30209513 597144025 1298354

9. 14 + 2 – 8 – 3  14 + 2 = 16  16 – 8 = 8  8 – 3 = 5  If you chose 5  cross it off!

10. 36 – 24 + 62 - 49  36 - 24 = 12  12 + 62 = 74  74 – 49 = 25  If you chose 25  cross it off!

11. 361 – 200 + 15 – 81  361 – 200 = 161  161 + 15 = 176  176 – 81 = 95  If you chose 95  cross it off!

12. 29 + 108 – 210 + 93  29 + 108 = 137  137 + 93 = 230  230 – 210 = 20  If you chose 20  cross it off!

13. 23 – 2 + 4 + 5  23 - 2 = 21  21 + 4 = 25  25 +5 = 30  If you chose 30  cross it off!

14. 105 + 23 – 78 – 50  105 + 23 = 128  128 – 78 = 50  50 – 50 = 0  If you chose 0  cross it off!

15. 27 + 6 – 11 – 9  27 + 6 = 33  33 – 11 = 22  22 – 9 = 13  If you chose 13  cross it off!

16. 952 – 1010 – 251 + 438  952 + 438 = 1390  1390 - 1010 = 380  380 – 251 = 129  If you chose 129  cross it off!

17. 17 + 4 – 9 – 3 – 5  17 + 4 = 21  21 – 9 = 12  12 – 3 = 9  9 – 5 = 4  If you chose 4  cross it off!

18. Find the difference between one hundred and ninety, and eighty-three. Then add on thirty-seven  190 – 83 = 107  107 + 37 = 144  If you chose 144  cross it off!

19. 124 + 51 – 78 – 14  124 + 51 = 175  175 – 78 = 97  97 – 14 = 83  If you chose 83  cross it off!

20. 612 – 318 + 219 + 84  612 – 318 = 294  294 + 219 = 513  513 + 84 = 597  If you chose 597  cross it off!

21. Homework for Tomorrow STP 7 Pg 4 Ex 1c 5,10,15 Pg 7 Ex 1e 5,17,24 Pg 9 Ex 1f 13, 17, 19