Query: What was the most popular sized disc by 1910?
Context: In the 1890s, the recording formats of the earliest (toy) discs were mainly 12.5 cm (nominally five inches) in diameter; by the mid-1890s, the discs were usually 7 in (nominally 17.5 cm) in diameter. By 1910 the 10-inch (25.4 cm) record was by far the most popular standard, holding about three minutes of music or other entertainment on a side. From 1903 onwards, 12-inch records (30.5 cm) were also sold commercially, mostly of classical music or operatic selections, with four to five minutes of music per side.