Question

При каких натуральных значениях x верно равенство : 16/40=x/5; 7/x=63/36; x/12=25/60?

Answer 1

16/40 = x/5 
16/40 = 8x/40 
16 = 8x 
x = 2 
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7/x = 63/36 
63/9x = 63/36
9x = 36 
x = 4 
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x/12 = 25/60 
5x/60 = 25/60
5x = 25
x = 5