Three Hundred
numeral
You have three hundreds. What does that come out to? Three hundred.
The reading is a little bit weird, so be careful. You should already know the on'yomi readings, but the ひゃく rendakus to びゃく. This pattern will repeat itself with 三 + many counter kanjis that can rendaku, so pay attention for it as you read Japanese.
三百人
three hundred people
三百台
300 units
三百才
300 years old
三百円です。
It's 300 yen.
大体三百人が来ました。
About 300 people came.
一年は三百六十五日です。
A year is 365 days.