According to Baidu question bank query, 47 tens (), get rid of () and get 300. The answer is 47* 10=470, (470-300)÷ 10= 17, so there are 47 tens in 470. Remove 17 to get 300. So it is 470.

Tips: This paper comes from the addition and subtraction test questions and answers within Unit 4 100, Volume 2, Senior One Mathematics, West Normal University Edition.