There are three classes planting trees in Grade 6 of experimental primary school. The number of trees planted in class 1 accounts for 14% of the total number of trees in the three classes. The ratio of trees planted in class 2 to class 3 is 3:4. The number of trees planted in class 2 is 24 less than that in class 3. How many trees are planted in each of the three classes?

24 ／ 4 − 34 = 96 (trees) 96-24 = 72 (trees) (96 + 72) ／ (1-14) × 14 = 168 × 43 × 14 = 56 (trees) a: 56 trees are planted in class one, 72 trees in class two and 96 trees in class three

Lx-1l + LX + 1L > 6 solution inequality

The discussion is divided into three situations
(1) When x ≤ - 1
Original inequality - (x-1) + [- (x + 1)] > 6
1-x -x-1>6
At 2x1
The original inequality X-1 + X + 1 > 6
2x>6
x>3
The solution of the inequality is x > 3
To sum up, the solution of the original inequality is X3

In the sales promotion, it is stipulated that three empty bottles should be exchanged for one bottle of drink. After buying 12 bottles of drink, he can exchange the empty bottle for another. How many bottles can he drink at most
How to calculate

12 / 3 = 4 (12 bottles can be replaced by 4 bottles), 4 / 3 = 1... 1 (4 bottles can be replaced by 1 bottle, and there is still 1 bottle left). If you borrow one bottle, you can get three bottles to exchange for one bottle and return this bottle
Total: 12 + 4 + 1 + 1 = 18 bottles

The equations a + 12 / a = 7, 5A = 3A + 6 and (2 + a) a = 15 are solved respectively

A + 12 / a = 7 A * a-7a + 12 = 0 (A-3) (A-4) = 0 a = 3 or a = 4 5A = 3A + 6 5a-3a = 6 2A = 6 a = 3 (2 + a) a = 15 A * a + 2a-15 = 0 (a + 5) (A-3) = 0 a = 3 or a = - 5

A passenger car and a passenger car drive from a to B at the same time. When the car runs half of the whole journey, the passenger car is 54 kilometers away from B. when the car reaches the terminal point, the passenger car will arrive at the terminal point
How many kilometers is the distance between a and B?

The distance between a and B is 90 km
Methods: the time from the car to the middle point is t, and the distance is L
When the time is 2T, the car reaches the destination and the bus runs 4 / 5, then when the time is t, the bus runs 2 / 5
That is 2Z / 5 = z-54, z = 90

How much is 3 / 8 plus 5 / 8? How much is 3 / 8 plus 5 / 8?

3/8+5/8 = 1
(3/8)+(5/8) = 1

On the map with a scale of 1:5000000, the distance between a and B is 5.4cm. If the speed of the car at 60km / h is 8:00 a.m
When is the time to arrive at place B?
Xiaolan's house plan is 14cm and 9cm wide on the scale of 1:100. Xiaolan's father is going to lay 0.6m square tiles on the floor of the house. How many such tiles do he need? If each tile costs 16 yuan, how much does Xiaolan's house cost to sell the tiles?

1. Let the actual distance be xcm5.4: x = 1:5000000, x = 5000000x5.4, x = 27000000, 27000000cm = 270km, 270 divided by 60 is equal to 4.5 (hours) 8 + 4.5 = 12.5 (hours). A: the time to reach B is 12.5 hours. 2. (1) let the actual length be xcm14: x = 1:100

X / 6 + (x + 2) / 4 + (22-2x) / 5 = 5 to solve the equation

First of all, denominator 6, 4 and 5, the least common multiple of these three numbers is 60
If both sides of the equation are 60 at the same time, there is: 10x + 15 (x + 2) + 12 (22-2x) = 60 * 5
Namely: (10 + 15-12 * 2) x + 15 * 2 + 12 * 22 = 300
(25-24)X=300-15*2-12*22
X=300-30-264
X=300-294
The solution is: x = 6

Given that a > 0, if three points a (1, - a), B (2, A2) and C (3, A3) in the plane are collinear, then a=______ ．

In the plane, three points a (1, - a), B (2, A2), C (3, A3) are collinear, so A2 + A2-1 = a3-a23-2, so a2-2a-1 = 0, because a > 0, so a = 1 + 2; so the answer is: 1 + 2

The sum of the two numbers is 11.63. Due to carelessness, Xiao Ming moved the decimal point of a number one place to the left to get 5.87. What are the original two numbers?

Let one number be x and the other be 11.63-x
If it's 10 times smaller than x
Then there is
x÷10+11.63-x=5.87
11.63-0.9x=5.87
0.9x=11.63-5.87
0.9x=5.76
x=6.4
11.63-x=5.23
So the first case is: 6.4 and 5.23, the decimal point moving to the left is 6.4
If 11.63-x is 10 times smaller
therefore
x+（11.63-x）÷10=5.87
x+1.163-0.1x=5.87
0.9x=5.87-1.163
0.9x=4.707
x=5.23
The result is the same
So the two numbers are 6.4 and 5.23, and the decimal point moving to the left is 6.4