Comcast Corp. reported better-than-expected financial results and added video customers again in the first quarter, extending a strong streak for the cable industry in a weak overall pay-TV market. The company added 53,000 video customers, compared with a loss of 8,000 in the prior-year quarter. Its quarterly profit rose to $2.13 billion, or 87 cents a share, up from $2.06 billion, or 81 cents a share, a year ago.