Only the equations are not calculated

Solution: Let A = x, B = y, C = z, and the equation is listed according to the title.

x+y+z=102*3 ①

y= ②z= ③

Substituting the equation into the equation to get it.

x+ is 6x=306

x=51

Because the average of A, B, and C is 102, then the sum of the three numbers is 102 3=306, and if A is x, then the equation is x+

Let A, B, and C be represented by x, y, and z respectively, then (x+y+z) 3=1202y=3x2z=7x

then x+x=60

Let A, B, and C be x, y, and z respectively

x+y+z=102

y=z=simultaneous solution x y z

Learn the first stick, hello :

Solution: Let the number of armor be x

x＋6x＝306

x＝51

Let A be x, then (x+ can be solved.

1. Set each fan x yuan, each ceiling fan y yuan 5x+4y=1440 x-y=45

2. Set Uncle Li to sell the beans x yuan, the green vegetables y yuan 15x+35y=78 x=2y3, set up warehouse A to transport x tons, and warehouse B to transport y tons, x+y=60 130+x=2(80+y).

4. The car transports a total of x tons of goods, and the board truck transports a total of 9x-15y=18 x=3y

If the table fan is X, the ceiling fan is X+45

5x+4*(x+45)=1440

If the ** of the green vegetables is x, then the ** of the beans is 2x

35x+15*2x=78

If a warehouse is set to transport x tons, then bin B is 60-x

130+x=2*(80+60-x)

The load capacity of the board car is x, then the load capacity of the car is 3x

9*3x-18=15x

1.The company buys 5 table fans and 4 ceiling fans for a total price of 1440 yuan, each table fan is 45 yuan more expensive than each ceiling fan, how much is each table fan and each ceiling fan?

Set each ceiling fan x yuan, then there are:

4x+5(x+45)=1440;

9x+225=1440;

9x=1215;

x=135;

ceiling fan 135 yuan, table fan 180 yuan;

2.Uncle Li picked 15 kilograms of beans and 35 kilograms of vegetables to sell in the vegetable market, and got a total of 78 yuan, the price of 1 kilogram of beans is twice that of 1 kilogram of vegetables.

If the green vegetable ** is x yuan, then there is:

35x+15×2x=78；

35x+30x=78；

65x=78；

x=；So green vegetable yuan, bean yuan;

3. There are 130 tons of grain in warehouse A, 80 tons of grain in warehouse B, and now there are 60 tons of grain that need to be transported in.

Set up a transport of x tons, then there are:

130+x=2(80+60-x);

130+x=280-2x;

3x=150;

x=50;A transports 50 tons, B transports 30 tons;

4.9 cars and 15 pallet trucks are used to transport a batch of goods, and the load capacity of each car is equivalent to 3 times that of the pallet truck, resulting in a total of 18 tons more than the pallet truck, how many tons of goods are transported by the car?

If the car transports a total of x tons, there are:

x/9=3×((x-18)÷15);

x/9=(x-18)/5;

5x=9x-162;

4x=162;

x=;Cars transported a total of tons.

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Solution: Suppose there are x cows and 2x pigs.

2x+x=66

Son = (35-5) 6 + 5 = 10 years old.

Suppose the son is x years old this year.

6(x-5)=35-5

Solution: Five years ago, my son was x years old.

35-5=6(x -5)