 <translate> There are 10 x 3 = 30 green chairs. The total number of blue and green chairs is 10 + 30 = 40. So, there are 40 - 13 = 27 white chairs. Therefore, there are 40 + 27 = 67 chairs in a classroom. Final answer: 67. <yor> 10 x 3 jẹ́ 30 àga alawọ̀. Àpapọ̀ iye àwọn àga aláwọ̀ búlúù àti aláwọ̀ ewé jẹ́ 10 + 30 = 40. Nítorí náà, 40 - 13 = 27 àga funfun. Nítorí náà, 40 + 27 = àwọn àga 67 ní kíláàsì kan. Ìdáhùn tó péye: 67. 