1/a+1/b=(a+b)/(ab)因为ab为24的倍数,而24＝4*6（4+6）的值最小,所以a/b＝4/6,a=(2/3)b又因为ab/(a+b)=24,将a换成（2/3）b得（2/3）b^2/(2/3b+b)=24,(2/3)b^2/(5b/3)=24,2b/5=24,b=60,a=(2/3)b=40a+b=60+40=100...