665:7x12

=95x12

=1140

150x153

195x165

800x1234

20x145

50x708

210:3

501:3

500:2

5010:5 

210x770

880x99

\(\dfrac{2}{7}:\dfrac{2}{3}\times8-\dfrac{4}{5}=\dfrac{2}{7}\times\dfrac{3}{2}\times8-\dfrac{4}{5}=\dfrac{24}{7}-\dfrac{4}{5}=\dfrac{120}{35}-\dfrac{28}{35}=\dfrac{92}{35}\)

ok 

ok

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