53.5×35.5＋53.5×43.2＋78.7×46.5
=53.5x(35.5+43.2)+78.7x46.5
=53.5x78.7+78.7x46.5
=(53.5+46.5)x78.7
=100x78.7
=7870
题目有点问题,我把78.5改成了78.7你检查一下题目,看是不是打错是78.5那35.5是不是35.3,再检查下,那错了哦是，不好意思打错了题目是53.5×35.3＋53.5×43.2＋78.5×46.5=53.5x(35.3+43.2)+78.5x46.5=53.5x78.5+78.5x46.5=(53.5+46.5)x78.5=100x78.5=7850