7.2*18+7.2*3-7.2=?18.2*102-18.2*3+18.2=?用递等式计算

问题描述:

7.2*18+7.2*3-7.2=?18.2*102-18.2*3+18.2=?用递等式计算

=7.2*(18+3-1) =7.2*20 =144 =18.2*(102-3+1) =18.2*100 =1820