26×（3/26+4/25）×25=26×25×（3/26+4/25）=26×25×3/26+26×25×4/25=75+104=179
26x(3/26+4/25)x25 = (3+4x26/25)x25= 3x25 + 4x26 = 75 + 104 = 179
