hala Snapshots Assessment Stage 5 and 6 (2)

Addition/Subtraction Stage 5 and 6

Solve the problems below. Try to use the strategy explained in the box above each question. Make sure you show all the steps you use to solve it.

Stage 5: Early Additive I can work out the answer by using my basic facts e.g. 8 + 7 is 8 + 8 – 1 (doubles) or 5 + 3 + 5 + 2 (fives) or 10 + 5  (making tens).

1. Sam had 8 lollies and Jackson had 7. How many have they got altogether?

8+7=15

8+8=16

16-1=15

Stage 5: Early Additive I can solve problems by splitting them into parts , e.g. 100’s, 10’s, 1’s  (partitioning) e.g. 43 + 25 = (40 + 20) + (3 + 5) = 60 + 8 = 68 (standard partitioning)

2. Rosa went on a road trip. She cycled 63 kms on day one and on day 2 she cycled 149 kms. How many  kms did she go over the two days?

149+63=212

140+60=200

9+3=12

200+12=212

Stage 5: Early Additive I can solve addition problems by rounding one to a tidy number by compensation (taking some from the other number) 39 + 26 = (39 + 1) + (26 - 1) =  40 + 25 = 65 (rounding and compensation)

3. Ms Reader  bought some new books for the school library. She bought 39  from one shop and 45 from another. How many books did she buy altogether?

39+45=84

30+40=70

9+5=14

70+14=84

Stage 5: Early Additive I can solve subtraction problems by splitting numbers into parts instead of counting down. e.g. 84 – 7 as 84 – 4 =                                 80 – 3 =  77 (back through ten).

4. There were 72 students at the softball tournament but then 7 had to leave early. How many were left?

72-7=65

72-2=70

7-2=5

70+5=65

Stage 6: Advanced Additive Estimate answers and solve addition and subtraction tasks involving whole numbers mentally by choosing appropriately from a broad range of advanced mental strategies

Stage 6: Advanced Additive: I can solve subtraction problems by equal additions that turn one of the numbers into a tidy number. Also I can solve problems by equal subtractions. e.g. 63 - 39 = (63 + 1) - (39 + 1) = 64 - 40 = 24,   So 63 - 39 = 24

5. There are 152 houses in the street. 38 houses have garages the rest don’t. How many don’t have a garage?

152+38=190

38+2=40

152-2=150

150+40=190

Stage 6: Advanced Additive: I can solve problems by splitting numbers into parts. e.g., 324 – 86 = 324 - 24 = 300 – 62 = 238  (24 and 62 = 86) (standard place value partitioning)

6. At Pepsi's school there are 243 students. 67 were  born in different countries so how many were born here?

243-67=

243-3=240

67-3=4

240+4=244

Stage 6: Advanced Additive: I can solve problems like 73 – 19 =  by first subtracting a tidy number then adding a small number to get the answer.   e.g., 63 – 39 = 63 – 40 + 1 = 24 (rounding and compensating)

8. 133 cars were parked in the carpark then 89 left. How many cars are still in the carpark?

133-89=44

123-90=43 + 1= 44

I know that problems like 34 + __  = 51 and 51 - 34 =  have the same answer. So for subtraction I can reverse the problem and then jump up tidy numbers on the number line to solve it, or jump up a tidy number then jump back. or 63 - 39 = 39 + __ = 63 39 + 20 + 4 = 63  so 63 – 39 = 24 (reversibility)

9. 142 children are in Parklane School’s senior classes. Of those 66 got driven to school while the rest walked. How many walked?

142 - 66=

142-60=62

62+6=68