31/32 * 3 1/5 + (8 5/9 * 6/35 + 3 8/15) * 3 8/15 = - вопрос №31323158596353815381571450519 от konfetabox 29.10.2020 18:20

Question

Математика: 31/32 * 3 1/5 + (8 5/9 * 6/35 + 3 8/15) * 3 8/15 = 7 решите по действиям пример: 1) 2) т.д.

konfetabox · Answer

(31/32)×3(1/5)+(8(5/9)×(6/35)+3(8/15))×3(8/15)=7- тождество не верное.

20(23/30)≠7

(31/32)×3(1/5)+(8(5/9)×(6/35)+3(8/15))×3(8/15)=20(23/30)

1) (31/32)×3(1/5)=(31×16/32×5)=(31×16/16×2×5)=(31/10)

2) 8(5/9)×(6/35)=(77/9)×(6/35)=(77×6/9×35)=(11×7×3×2/3×3×7×5)=(11×2/3×5)=(22/15)

3) (22/15)+3(8/15)=(22/15)+(53/15)=(22+53)/15=(75/15)

4) (75/15)×3(8/15)=(75/15)×(53/15)=5×(53/15)=(5×53)/3×5=(53/3)

5) (31/10)+(53/3)=(31×3+53×10)/30=(93+530)/30=623/30=20(23/30)

20(23/30)≠7