Please help solve the math problems, thank you

This question should be limited by adding common sense.

Assuming that the ten digits of Xiao Ming's grandfather's age are integers x, and the number of each digit is the integer y, then.

Grandpa Xiao Ming's age is 10x y

Xiao Ming's father's age is 10y x

Since Xiao Ming's grandfather's age must be greater than Xiao Ming's father's age, x>y

Ming's age (10x y 10y x) 4 9 (x y) 4

According to common sense, Xiao Ming's father should be more than 22 years older than Xiao Ming, assuming x y 1, then Xiao Ming's grandfather is only 9 years older than his father, which is unlikely according to common sense.

Assuming x y 2, then Grandpa Ming is 18 years older than his father, and Ming is a year old, and the ages of Grandpa Ming and Dad may have the following combinations: 53 35 64 46 75 57 Others are unreasonable.

Suppose x y 3, then Grandpa Ming is 27 years older than his father, and Ming is old.

The ages of Grandpa and Dad may have the following combinations: 63 36 74 47 85 58 Other irrationalities.

Assuming x y 4, Grandpa Ming is 36 years older than his father, and Ming is 9 years old.

The ages of Grandpa and Dad may have the following combinations: 73 37 84 48 95 59 Others are unreasonable.

Assuming x y 5, then Grandpa Ming is 45 years older than his father, and Ming is old.

The ages of Grandpa and Dad may have the following combinations: 83 38 94 49 Others are unreasonable.

Assuming x y 6, then Grandpa Ming is 54 years older than his father, and Ming is old.

The ages of Xiao Ming's grandfather and father may have the following combinations: 93 39 Others are unreasonable.

When x-y>=7, there is no common age combination, so it is not considered.

If Xiao Ming's age must be an integer, then Xiao Ming is 9 years old.

Let the grandfather's age be ab, =10a+b

Then the father is ba, =10b+a

Then 10a+b-(10b+a) can be divisible by 4, that is, 9 (a-b) can be divisible by 4, because a and b are singular between 0-9, so the difference must be less than 9, so the value of a-b can be divisible by 4, 4 or 8, if it is 4, then Xiao Ming is 9 years old this year, grandpa 84 father 48 or grandpa 95 father 59 (slightly outrageous), which is normal;

If you take 8, then the grandfather is 91 and the father is 19, and Xiao Ming is 18, which is completely outrageous, so Xiao Ming's age is certain, 9 years old.

Assuming that Xiao Ming's grandfather's age number is ab, Xiao Ming's age is mab-ba=4m

10a+b-10b-a=4m

9a-9b=4m

9(a-b)=4m

The difference between a-b is a multiple of 4 (it can't be 0, otherwise grandpa is the same age as dad) because a and b are the same number, then the difference between a-b may be: 4,8, when a-b = 4, m = 9, grandpa is 84 years old, dad is 48 years old; Or Grandpa is 95 years old and Dad is 59 years old.

When a-b=8, a=9, b=1,-- grandpa is 91 years old, dad is 19 years old, and Xiao Ming is 18 years old.

A: Xiao Ming is 9 years old.

"The speed of the vehicle must be increased by 5 kilometers per hour". Because there was a 30-minute stop in between, you had to speed up to get there on time.

Regardless of whether there is an accident or not, the total amount of time and distance is the same! Let's get this done first.

Solution: Let the original speed of the car be x km/h, and the speed after being blocked x+5 km/h.

180/x=180/（x+5）+

Normal travel time = acceleration travel time + parking time).

180（x+5）=180x+

180x+900=180x+squared+

x=40 or -45 kmh.

x=40 kmh.

x+5=45 kmh.

A: The car arrives at point B at a speed of 45 km/h.

Let the subsequent speed of the car be x kilometers per hour, then the original speed of the car is x-5 According to the topic, the original speed is used to travel from the unexpectedly blocked place to place B, and the time required for 180 kilometers is subtracted from 30 minutes (hours) to equal the time required to travel 180 kilometers at the subsequent speed.

The equation is: 180 (x-5) -= 180 x, i.e., x 2-5x -1800=0

x-45)(x+40)=0

Solve the equation as: x=-40 (undesirable, the velocity cannot be negative) or x=45 So, the subsequent velocity of the car is. 45 kmh.

The speed of the car must be increased by 5 kilometers per hour, which means that the acceleration is 5, now you know the solution.

The speed of the vehicle must be increased by 5 kilometers per hour, which means that the acceleration a = 5 kilometers Hour solution: Let the original speed be v, and the time to reach the place b at the blocked place at the speed is t, then there is:

vt=180v（

The remaining 180 km/h is correct to travel at a constant speed (V+5) km/h!

Solution: Let the original velocity be vkm h, and the increase rate is (v+5)km h, then:

180/v=180/(v+5)+1/2

180（v+5)=180v+(v+5)v/2v^2+5v=1800

v+v+v1=40 v2=-45 (rounded), that is, after the growth rate, it is (v+5)=40+5=45km h.

"The speed of the vehicle must be increased by 5 kilometers per hour" means that after the blockage, the speed of the vehicle must be increased by 5 kilometers per hour, and it will be able to reach place B at the original time.

It can be obtained by setting the speed of the vehicle to point B as x.

180 x)+1 2=180 (x-5) and then solve to get the value of x (the speed can only be positive, so the answer is only one head.)

Suppose the speed of the car to reach place B is x kilometers per hour, and the original speed is x - 5 kilometers per hour 180 x = 180 (x-5)-30 60180 (x-5) = 180x-x(x-5) 2x(x-5) 2 = 900

x(x-5)=1800

x^2-5x-1800=0

x-45)(x+40)=0

x1=45 x2=-40

The speed of the car to reach point B is 45 km/h.

Let's assume that the remaining 180 kilometers of the original run will be at a speed and the time taken will be b hours. Then ab=180

Now the time is delayed by 30 minutes, which means that if you want to be on time, the time used is that the speed is A+5, and the speed must be increased by 5 kilometers per hour, that is, the current speed is 5 kilometers per hour faster than the original speed.

In this way(a+5)(, we can solve the equation that a=40 km/h.

Just set an equation.

Three-dimensional once is very simple.

Question 1:

The unit prices of the three combinations are:

A = 2 * 2 + yuan;

B = 2 * 3 + yuan;

C = 2 * 2 + yuan;

The number of sets of three combinations of fruits sold is: X, Y, and Z.

Then: 4x+6y+4z=116

Multiply by two formulas to get:

Subtract the previous formula from one formula to get :

Therefore: y+z=15, that is, the two combinations of B and C have sold a total of 15 sets.

Since the C fruit in the two sets of combinations B and C is 1 kg, so. c Fruit sold 15 kg.

Question 2: The number of people who grow three kinds of vegetables is x, y, and z. Then:

x+y+z=20

2x+3y+4z=50

Multiply by 2 to get 2x+2y+2z=40

Subtract the previous formula from the second formula: y+2z=10, and introduce y=10-2z into a formula: x+10-2z+z=20, and launch:

x=z+10 In order to make the total crop output value the highest, it is known from the table given that there should be as many vegetables as possible, followed by wheat and tobacco leaves. Therefore, it is necessary to make x the largest, z second, and y the smallest as much as possible.

From y=10-2z, x=z+10 and x+y+z=20, the minimum z is 0 and the maximum is 5; x is 15 at maximum and 10 at minimum; The maximum y is 10 and the minimum is 0;

So the possible values of x, y, z are:

When x=10, y=10, z=0

When x=11, y=8, z=1;

When x=12, y=6, z=2;

When x=13, y=4, z=3;

When x=14, y=2, z=4;

When x=15, y=0, z=5;

Therefore, in order to achieve the highest total value, choose the last planting plan, that is, 15 people grow vegetables and 5 people grow wheat; The total output value can reach 15 * 2 * 1 + 5 * 4 * 10,000 yuan.

The first purchase of x pieces, the second purchase of 2x pieces.

So 80000 x + 4 = 176000 2x solution x = 2000, so a total of 3x = 6000 pieces.

The first time: the cost of 80000 2000 = 40 yuan, 58-40 = 18 yuan, 18 * 2000 = 36000 yuan.

The second time: cost 40 + 4 = 44 yuan, 58-44 = 14 yuan, 14 * (6000-150) = 81900 yuan, 58 * yuan, yuan, a total of 36000 + 81900 + 360 = 118260

Solution: Let the mass of the apples in the first frame be x kilograms.

x=180+200=380kgA.

Set twice the width of the colored paper to x

18+x）(12+x)=18*12(1+2/3)（18+x）(12+x)=360

Calculate for yourself below.