Question

99/100X99 简便计算两种方法解答 5/3X3/13+5/9X3/13+5/18X6/13 注：X是乘号,不是方程

Answer 1

99/100X99=(100-1)/100×99=1×99-1/100×99=99-99/100=98又1/100

99/100X99=99/100×(100-1)=99/100×100-99/100×1=99-99/100=98又1/100

5/3X3/13+5/9X3/13+5/18X6/13

=5/13+5/13×1/3+5/13×1/3

=5/13×(1+1/3+1/3)

=5/13×5/3

=25/39