养鸡场养鸡350只,与鸭的只数比是5:7,鸡和鸭的总数相当于鹅只数的12/11,养鹅多少只?

问题描述:

养鸡场养鸡350只,与鸭的只数比是5:7,鸡和鸭的总数相当于鹅只数的12/11,养鹅多少只?

(350+350*7/5)*11/12

(350+350x7/5)÷12/11
=(350+490)÷12/11
=840÷12/11
=770
答:养鹅770只

350÷5=70
70×7+350=840
840×12/11=770