3.4*6.7+1.7*6.6简便运算怎么做3.4*6.7+1.7*6.6=3.4*6.7+1.7*2*3.3=3.4*（6.7+3.3）=3.4*10=34
解：3.4*6.7+1.7*6.6= (10-6.6)*6.7+1.7*6.6=67-6.6*6.7+1.7*6.6=67-(6.7-1.7)*6.6=67-5*6.6=67-33=34
