养鸡场养了公鸡比母鸡少180只,公鸡的只数比母鸡少60%,母鸡有多少只?

问题描述:

养鸡场养了公鸡比母鸡少180只,公鸡的只数比母鸡少60%,母鸡有多少只?

假设公鸡为X 母鸡为Y
y-x=180
x=y-60%y
y-(y-60%y)=180
y-(y-0.6y)=180
y-y+0.6y=180
0.6y=180
y=180/0.6
y=300
x=120

母鸡有 180÷60%=300只

公鸡设为X,母鸡设为Y.
x+180=y.
x=(1-60%)y.
x=40%y.
40%y+180=y;
180=60%y;
y=300只.
x=40%y=120只.

设母鸡x只,公鸡x-180只
0.4x=x-180
-0.6x=-180
x=300
答:母鸡300只