Question

十五分之七除以九加九分之一乘十七分之十二（简便计算）？

Answer 1

简便计算
5/17÷9+1/9x12/17
=5/17x1/9+12/17x1/9
=（5/17+12/17）x1/9
=1x1/9
=1/9

Answer 2

7/15÷9+1/9×12/17
=7/15×1/9+1/9×12/17
=1/9×(7/15+12/17)
=1/9×(7×17+12×15)/255
=1/9×299/255
=299/2295