Companies listed on the first section of the Tokyo Stock Exchange posted a 47.5 percent year-on-year rise in group pretax profit as a whole in the April-June quarter, the Shinko Research Institute said Monday.

Combined sales rose 7.7 percent in the first quarter from a year earlier, the think tank said in a report on consolidated quarterly results released by 433 companies as of Friday.

By business, companies in the electrical machinery sector saw their pretax profits increase fourfold from a year earlier due to strong sales of digital products such as flat TVs and DVD recorders.