255e24c08876e69b6065534aab99eab4.ppt
- Количество слайдов: 193
0. 016 3 0. 048
0. 0091 5 0. 0455
8. 3 2. 9 747 + 166 24. 07
0. 12 5. 3 36 + 60 0. 636
0. 029 1. 8 232 + 29 0. 0522
$14. 60 15. 75 7300 10220 7300 + 1460 229. 9500
Estimate to find the weight of each whale in pounds and then subtract to find a reasonable estimate of the difference.
Blue whale: 2, 000 × 151 2, 000 300, 000 – 80, 000 = 220, 000 Humpback whale: 2, 000 × 38. 1 80, 000
Look back at the problem. A blue whale weighs about 150 – 40 or 110 more tons than a humpback whale. This is equal to 110 × 2, 000 or 220, 000 pounds. So the answer is reasonable.
2. 4 3 7. 2 – 6 12 – 1 2 0
0. 44 15 6. 60 – 0 66 – 6 0 60 – 60 0
First, add all the data together. 6. 22 6. 00 6. 11 + 6. 11 24. 44 Divide by the number of addends to find the mean mass. 6. 11 4 24. 44
6. 4 21. 44 3. 34 64 214. 40 – 192 22 4 – 19 2 3 20 – 3 20 0
21. 44 divided by 6. 4 is 3. 34 × 6. 4 = 21. 44
0. 4 72. 0 180. 4 720. – 4 32 – 32 00 – 0 0
2. 4 0. 024 0. 01 24 0. 24 – 0 02 – 0 24 – 24 0
42. 88 786. 85
18. 35 42. 88 78685. 00 – 4288 35805 – 34304 1501 0 – 1286 4 2146 0 – 2144 0 20
Make an organized list to see the different possibilities and use estimation to be sure he spends about $15.
Check the list to be sure that all of the possible combinations of sporting good items that total no more than $15 are included.
1 5 Find a multiple of 5 that is close to 16. 1 5 1 5
1 4 Find a multiple of 4 that is close to 23. 1 4 1 4
1 4 3 4
4 5 1 6 1 6 = 1 6 4 5 1 6
Round each mixed number to the nearest whole number.
6 7 8 2 1 4
1 5 1 6 = 1× 1 5× 6 = 1 30
1 2 5 8 = 5 8 1 2 7 1 5× 7 = 8× 1 = 35 3 or 4 8 8
3 8 1 2
1 2 3 7 3× 2 2 = 9 7× 9 6 2 = or 63 21
2 21
3 4 = 2 3 3× 2 4× 3 1 = 2 3 4 2 3 1 2
1 2 3 8 1 3 = 3 8 10 3 = 3 × 10 8× 3 = 5 or 1 1 4 4 1 3 10 3 1 2
1 5 1 2
1 5 1 21 = 2 5 3 2 = 21 × 3 5× 2 = 63 or 6 3 10 10 3 10
4 5 3 4 = 15 4 14 5 = 21 or 10 1 2 2
Since, 8 × 1 1 = 1, the reciprocal of 8 is. 8 8 1 8
Since, 5 5 3 3 × = 1, the reciprocal of is. 3 3 5 5 5 3
1 3 5 1 = 6 3 = 1× 6 3× 5 = 2 5 6 5
1 5 = 6 1 30 or 30 = 1
Divide 3 into 4 equal parts. 4
3 4 1 4 3 = 4 1 4 = = 3 16
1 4 1 25 = 2 4 5 2 25 4 2 5 =
= 25 4 2 5 = 5 or 2 1 2 2
5 8 2 3 = 21 8 3 2 = 63 or 3 15 16 16 = 2
3 4 = 180 1 15 4
= 180 1 = 720 15 = 48 4 15
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