简便计算:129*127/128+127*129/128

问题描述:

简便计算:129*127/128+127*129/128

129*127/128+127*129/128
=(128+1)乘以127/128+(128-1)乘以129/128
=127+127/128+129-1-1/128
=255+126/128
=255又63/64