X-640=921: 3 x : 9 = 2007: 9 x* 81=729: 3

Question

X-640=921: 3
x : 9 = 2007: 9
x* 81=729: 3

Answer 1

1)х-640=921:3
х-640=307
х=640+307
х=947
2)х:9=2007:9
х:9=223
х=223•9
х=2007
3)х•81=729:3
х•81=243
х=243:81
х=3

Comments

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