如题所述
第1个回答 2020-10-08
∵ a÷13余5;b÷13余9
∴ a=13m+5; b=13n+9
∴ (a+b)÷13 = [(13m+5)+(13n+9)]÷13
=[13(m+n)+14]÷13
=[13(m+n+1)+1]÷13
=m+n+1.......1(余数1)
∴ a=13m+5; b=13n+9
∴ (a+b)÷13 = [(13m+5)+(13n+9)]÷13
=[13(m+n)+14]÷13
=[13(m+n+1)+1]÷13
=m+n+1.......1(余数1)