Question

2/5 + 7/15 - 1/3
3/5 + 2/3 + 4/10
2/7 + 1/2 - 2/3
3/8 - 1/3 + 3/4
5/12 + 1/6 + 3/9
(COM MMC me ajudem pfvvv)​

Answer 1

Resolução!

■ 2/5 + 7/15 - 1/3

5 , 15 , 3 / 3

5 , 5 , 1 / 5

1 , 1

MMC => 3×5 = 15

= 2/5 + 7/15 - 1/3 _____ MMC = 15

= 6 + 7 - 5/15

= 13 - 5/15

= 8/15

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■ 3/5 + 2/3 + 4/10

5 , 3 , 10 / 2

5 , 3 , 5 / 3

5 , 1 , 5 / 5

1 , 1 , 1

MMC => 2×3×5 = 30

= 3/5 + 2/3 + 4/10 _____ MMC = 30

= 18 + 20 + 12/30

= 50/30 ÷ 10

= 5/3

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■ 2/7 + 1/2 - 2/3

7 , 2 , 3 / 2

7 , 1 , 3 / 3

7 , 1 , 1 / 7

1 , 1 , 1

MMC => 2×3×7 = 42

= 2/7 + 1/2 - 2/3 _____ MMC = 42

= 12 + 21 - 28/42

= 33 - 28/42

= 5/42

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■ 3/8 - 1/3 + 3/4

8 , 3 , 4 / 2

4 , 3 , 2 / 2

2 , 3 , 1 / 2

1 , 3 , 1 / 3

1 , 1 , 1

MMC => 2×2×2×3 = 24

= 3/8 - 1/3 + 3/4 ______ MMC = 24

= 9 - 8 + 18/24

= 1 + 18/24

= 19/24

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■ 5/12 + 1/6 + 3/9

12 , 6 , 9 / 2

6 , 3 , 9 / 2

3 , 3 , 9 / 3

1 , 1 , 3 / 3

1 , 1 , 1

MMC => 2×2×3×3 = 36

= 5/12 + 1/6 + 3/9 ____ MMC = 36

= 15 + 6 + 12/36

= 33/36 ÷ 3

= 11/12

Espero ter ajudado