On-line solution of mathematics problems in the fifth grade of primary school (complete equation)

1. Analysis: If there are x chickens, then each chicken has 2X feet; There are x chickens, 6-X rabbits and 4(6-X) rabbits with one foot.

Solution: If the chicken has X heads, the rabbit has 6-X heads.

4(6-X)= 1

The solution is X=2.

Then there are 2 chickens, 6-2=4 rabbits.

2. Analysis: The same reason

Solution: If the chicken has X heads, the rabbit has 1 1-X heads.

4( 1 1-X)= 1

The solution is X=4.

Then there are 4 chickens, 1 1-4=7 rabbits.

3. solution: if the number of chickens is x, the number of rabbits is 5-X.

4(5-X)= 14

The solution is X=3.

Then there are 3 chickens and 5-3 rabbits = 2.

4. Analysis: Same as above

Red+green = 14kg,

Red 1 kg 120 yuan, how much red is (120* red) yuan and green is (160* green) yuan.

Solution: let black tea be x kg and green tea be 14-X kg.

120X

160( 14-X)= 1

2080

The solution is X=4.

Then black tea is 4 kg, and green tea is 14-4= 10 (kg).