亮亮有40张纸，折纸飞机用去13张，后来又用去9张，共用去多少张纸？8[3?:D)k0k8d5b4_7[9X-t8m'_
算式：提示7R1j)M*C9b4m8[3?:D)k0k8d5b4_7[9X-t8m'_
答：共用去6n9`5D4q8E-J1D/n-U:[6g;C*Z+X张纸。8[3?:D)k0k8d5b4_7[9X-t8m'_