[tex] \frac{1}{60} :(- \frac{1}{30} )-(- \frac{6}{10} )=[/tex]
[tex] =\frac{1}{60} x(- \frac{30}{1} )+ \frac{6}{10}=[/tex]
[tex] = -\frac{1}{2} + \frac{6}{10}=[/tex]
[tex]= -\frac{5}{10} + \frac{6}{10}=[/tex]
[tex]=\frac{1}{10} [/tex]
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Suma- Suma*65%=175
S-S*65/100=175
S*100/100-S*65/100=175
S*35/100=175
S*35=17500
S=17500:35
Suma =500