解13/16×(9/13×17-9/13)
=13/16×9/13×(17-1)
=13/16×9/13×16
=9
13/16×(9/13×17-9/13)
=13/16X9/13X(17一1)
=13/16X9/13X16
二9
解:原式=13/16×(153/13-9/13)
=13/16×144/13
=144/16
=9
13/16×(9/13×17-9/13)
=13/16×9/13×(17-1)
=13/16×13/9×16
=9