39乘37/38+37乘1/38

39乘37/38+37乘1/38

39乘37/38+37乘1/38
=39乘37/38+37/38
=(39+1)×37/38
=(38+2)×37/38
=38×37/38+2×37/38
=37+37/19
=38又18/19