Week 9 Reflection

Maths

This is a little more/less sheet that we were meant to work with a buddy and I worked with James to learn rounding compensation strategies

Exercise 5

What to do   

Use the information given to you to derive the answer to a similar problem.

1. If 4 × 200 = 800 what is 4 × 201 804
2. If 7 × 300 = 2100 what is 7 × 301 2107
3. If 8 × 400 = 3200 what is 8 × 402 3216
4. If 9 × 500 = 4500 what is 9 × 501 4509
5. If 5 × 600 = 3000 what is 5 × 602 3010
6. If 3 × 700 = 2100 what is 3 × 704 2112
7. If 2 × 800 = 1600 what is 2 × 803 1606

8) If 6 × 900 = 5400 what is 6 × 903 5418

Exercise 6

What to do   

Use the information given to you to derive the answer to a similar problem.

1. If 4 × 200 = 800 what is 4 × 199 796
2. If 7 × 300 = 2100 what is 7 × 299 1093
3. If 8 × 400 = 3200 what is 8 × 398 3184
4. If 9 × 500 = 4500 what is 9 × 498 4482
5. If 5 × 600 = 3000 what is 5 × 597 2985
6. If 3 × 700 = 2100 what is 3 × 698 2094
7. If 2 × 800 = 1600 what is 2 x 797 1594
8. If 6 × 900 = 5400 what is 6 × 897 5382

Exercise 7

What to do   

Use the information given to you to derive the answer to a similar problem.

1. If 2 × 25 = 50 what is 2 × 24 48
2. If 4 × 25 = 100 what is 4 × 27 108
3. If 3 × 15 = 45 what is 3 × 14 42
4. If 4 × 15 = 60 what is 4 × 17 68
5. If 6 × 15 = 90 what is 6 × 14 84
6. If 2 × 25 = 50 what is 2 × 26 52
7. If 4 × 25 = 100 what is 4 × 24 96
8. If 3 × 15 = 45 what is 3 × 16 48
9. If 4 × 15 = 60 what is 4 × 13 52
10. If 6 × 15 = 90 what is 6 × 17 102

Exercise 8

What to do   

Use the strategy add a little/subtract a little to solve these problems.  

Julie wanted to find 3 × 28.

She knows that 28 is near 30, so she used 3 × 30 = 90 and subtracted 3 × 2 = 6 to get the answer.  

Julie recorded this in her maths book

3 × 28 = 90 – 6 = 84

Using Julie’s method find the answer to the following problems.  Record your working like Julie did.

1) 4 × 19 76 (2) 3 × 41123 (3)  5 × 59 295

4) 7 × 52 134 (5) 4 × 73  292 (6)     3 × 37 111

7) 6 × 102 612 (8) 5 × 301 1505      (9)     4 × 698  2792

10) 3 × 499 1497 (11) 7 × 602 4214 (12) 9 × 3999 35991

I learn't how to use Rounding Compensation

Reading

We are learning about water pollution.

I learnt that there is solutions to the water problems our creeks face today.