Răspuns :
356 + a - 248 = 236
a = 236 + 248 - 356
a = 128
a + (875 - 629) = 794
a = 794 - 246
a = 548
356+a-248=236
a=236+248-356
a=128
356+128-248=236
a+(875-629)=794
a=794-246
a=548
548+(875-629)=794
a=236+248-356
a=128
356+128-248=236
a+(875-629)=794
a=794-246
a=548
548+(875-629)=794