Answer

Hamming (7,4): Parity bits at 1,2,4. Received 1011010, even parity checks: $p_1=1\oplus1\oplus0\oplus0=0$, $p_2=0\oplus1\oplus1\oplus0=0$, $p_4=1\oplus0\oplus1\oplus0=0$ syndrome 000 → no error. Data bits 3,5,6,7 =1010. If odd parity syndrome 111 → position 7 error. Method: syndrome binary = error position, flip.