Question

на ферме имеются куры и овцы, на сколько кур больше чем овец если вместе 920 голов и 2120 ног.

Answer 1

У курицы 2 ноги, у овец 4, у обеих одна голова. Вот и нужно составить систему уравнений. 
х-число овец, у-кур 

х+у=920 
4х+2y=2120

Answer 2

Problem Analysis

We are given that there are chickens and sheep on a farm, and we need to determine how many more chickens there are than sheep. We are also given that there are a total of 920 animals and 2120 legs on the farm.

Solution

Let's assume that the number of chickens is represented by x and the number of sheep is represented by y. We can set up the following equations based on the given information:

1. x + y = 920 (equation representing the total number of animals) 2. 2x + 4y = 2120 (equation representing the total number of legs)

We can solve this system of equations to find the values of x and y.

Solving the System of Equations

To solve the system of equations, we can use the method of substitution or elimination. Let's use the method of substitution:

From equation 1, we have x = 920 - y.

Substituting this value of x into equation 2, we get:

2(920 - y) + 4y = 2120 1840 - 2y + 4y = 2120 2y = 2120 - 1840 2y = 280 y = 140

Substituting the value of y back into equation 1, we get:

x + 140 = 920 x = 920 - 140 x = 780

Answer

Therefore, there are 780 chickens and 140 sheep on the farm. The number of chickens is 640 more than the number of sheep.

Verification

Let's verify our answer by checking if it satisfies both equations:

1. x + y = 920 780 + 140 = 920 (satisfied)

2. 2x + 4y = 2120 2(780) + 4(140) = 2120 (satisfied)

Therefore, our answer is correct.

Conclusion

On the farm, there are 780 chickens and 140 sheep. The number of chickens is 640 more than the number of sheep.