7/3-4/3÷8/5 et -4/9×1/5+3/7 merci d'avance
Mathématiques
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Question
7/3-4/3÷8/5 et -4/9×1/5+3/7 merci d'avance
2 Réponse
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1. Réponse maudmarine
Bonsoir,
7/3-4/3÷8/5
= 7/3 - 4/3 x 5/8
= 7/3 - 20/24
= (7 x 8) / (3 x 28) - 20/24
= 56/24 - 20/24
= 36/24
= (12 x 3) / (12 x 2)
= 3/2.
-4/9×1/5+3/7
= - 4/45 + 3/7
= (- 4 x 7) / (45 x 7) + (3 x 45) / (7 x 45)
= - 28/315 + 135/315
= 107/315 -
2. Réponse loulakar
Bonsoir,
A = 7/3-4/3÷8/5
A = 7/3 - 4/3 x 5/8
A = 7/3 - 4/8 x 5/3
A = 7/3 - 1/2 x 5/3
A = 14/6 - 5/6
A = 9/6
A = 3/2
B = -4/9×1/5+3/7
B = -4/45 + 135/315
B = -28/315 + 135/315
B = 107/315