four hundred-odd?=420 or =320

[gxiang]

in a passage, i read a discription.

i could get about 100 pounds for the old car, now i would need another four hundred-odd, three hundred and twenty to buy a newer one.

i thought it should be four hundred and twenty, or am i wrong. i don't understand what does "odd" mean here? it's the first time i see this usage.
thx:)

[Tdol]

odd = approximately, about

[gxiang]

Dear Tdol, Thank you very much for your kind reply.