Is the equation ok?

Let's take out x yuan. The column equation is (5400-X)=3(3800-X), and the equivalence relation: after taking out the deposit, Xiao Zhang is three times that of Xiao Wang, and the solution is 3000.

I see. Take out 3000 and use 5400-3000=2400, 3800-3000=800.

Arithmetic method

The balance of deposits will not change after the same money is withdrawn, so 5400-3800= 1600 is used.

According to Xiao Zhang's deposit is 3 times that of Xiao Wang, it is concluded that Xiao Zhang is 3 times, Xiao Wang is 1 times, and Xiao Wang is 3- 1=2 times less. Divide the difference of 1600/(3- 1) by the multiple of the difference to get the double amount, that is, 800 yuan. Xiao Wang 800 yuan, 800*3=2400 yuan, Xiao Zhang 2400 yuan.

2. Let A have the original 2x yuan and B have the original x yuan. 2x- 1540 = x-600。

Arithmetic method

Deposit balance: 1540-600 = 940 yuan.

A is 2 times, B is 1 times, and the difference is 1 times.

Use 940/(2- 1) = 940 to find the amount of money of B, which is 1 times.

940 * 2 = 1880, A's money.

3. This problem is easy to use equations and X people.

Each person planted 4 trees, that is, 4x, and there are 7 trees left, that is to say, 7 trees are not planted, and they are listed as 4x+7;

If each race has five trees, that is, 5x, then two trees are missing, that is, the original trees are all planted, and two more trees can be planted, that is, two trees of various kinds, so 5x-2 should be used.

Both expressions are trees, and the number of trees is equal, so 4X+7=5X-2.

As for the tree tree, just bring X in.

4。 Question 4 and question 5 are of the same type.