Decimal ?? - Mailing list pgsql-sql

I have table :
create table test (name text, price numeric(6,2));
CREATE
insert into test values ('John',0.75);
INSERT

select * from test;
name | price
---------
John |  0.75 

but when i insert into test values ('John',3/4);
INSERT

select * from test;
name | price
---------
John |  0.00   --->  ??? 

why this value 0.00 but i want to 0.75 ??? help me please.

i am using mandrake 7 and postgres 6.5.3

Thanks
Nizomi