Today’s Chinese Slang is 八九不离十（ba jiu bu li shi ). It means mostly correct, pretty close. It is related to the number 8 and number 9, literally means eighty percent or more right. Examples:

tā měi cì de ɡū suàn dōu bā jiǔ bù lí shí 她 每 次 的 估 算 都 八 九 不 离 十 。

Her prediction are mostly correct.