Rounding issues?

Try this: create table test (f float); insert into test values (330.0); commit; select (8 + 330.0/60)::int; --14 select (8 + f/60)::int from test; --14 select (9 + 330.0/60)::int; --15 select (9 + f/60)::int from test; --14 Can someone explain why the last query returns 14 instead of 15? PostgreSQL 9.3.9 on x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3, 64-bit 12.04.5 LTS (GNU/Linux 3.2.0-63-virtual x86_64)