Re: rounding problems

As i'm playing around with rounding and the numeric field precision ran
into a odd set of results i don't understand

here is the sql i wrote the first four inserts are calculations we run
everyday and they make sense but if division is used the results are
not right or am i missing something

create table test_num (
num1 numeric(20,1),
num2 numeric(20,2),
num3 numeric(20,3),
num4 numeric(20,4),
num5 numeric(20,5),
num6 numeric(20,6),
num7 numeric(20,7),
num8 numeric(20,8),
num9 numeric(20,9));

delete from test_num;

insert into test_num values ( (0.70 *1.05), (0.70 *1.05), (0.70 *1.05),
(0.70 *1.05), (0.70 *1.05), (0.70 *1.05),
(0.70 *1.05), (0.70 *1.05), (0.70 *1.05));

insert into test_num values ( (0.709 *1.05), (0.709 *1.05), (0.709 *1.05),
(0.709 *1.05), (0.709 *1.05), (0.709 *1.05),
(0.709 *1.05), (0.709 *1.05), (0.709 *1.05));

insert into test_num values( (.5/.03), (.5/.3), (.5/3),
(.5/30), (.5/300), (.5/3000),
(.5/30000), (.5/30000), (.5/30000));

insert into test_num values( (.5/.03)*.9975, (.5/.3)*.9975, (.5/3)*.9975,
(.5/30)*.9975, (.5/300)*.9975, (.5/3000)*.9975,
(.5/30000)*.9975, (.5/30000)*.9975, (.5/30000)*.9975);

insert into test_num values( (9*.1),
(9*.01),
(9*.001),
(9*.0001),
(9*.00001),
(9*.000001),
(9*.0000001),
(9*.00000001),
(9*.000000001));

insert into test_num values ( (9/10),
(9/100),
(9/1000),
(9/10000),
(9/100000),
(9/1000000),
(9/10000000),
(9/100000000),
(9/1000000000));

insert into test_num values( (1*.1),
(1*.01),
(1*.001),
(1*.0001),
(1*.00001),
(1*.000001),
(1*.0000001),
(1*.00000001),
(1*.000000001));

insert into test_num values ( (1/10),
(1/100),
(1/1000),
(1/10000),
(1/100000),
(1/1000000),
(1/10000000),
(1/100000000),
(1/1000000000));

select * from test_num ;