I am currently working through みんなの日本語 (and still very new), in 第二課の会話 one character says "...408のサントスです。”, but in the audio the voice actor says what sounds like ”よんまるはちのサントスです".
I would say 408 as "よんひゃくはち" , what is this "まる", is it just another way to represent 100?