Fie a si b cele doua sume. a+b=234
[tex] \frac{1}{2}(a- \frac{1}{7}a)=b+ \frac{1}{7}a [/tex]⇔
[tex]\frac{1}{2}( \frac{7}{7} a- \frac{1}{7}a)=b+ \frac{1}{7}a [/tex]⇔
[tex]\frac{1}{2}( \frac{6}{7} a)= \frac{7}{7} b+ \frac{1}{7}a [/tex]⇔
[tex]\frac{3a}{7}= \frac{7b+a}{7} [/tex]⇔3a=7b+a⇔2a=7b
a+b=234⇔2a+2b=2*234⇔2a+2b=468
7b+2b=468
9b=468
b=468:9
b=52
a=234-52
a=182
