-
If the ten digits are x, then the single digit is 2x
So the original number is 10x+2x
After modulation, it is 10*2x+x
So (10*2x+x)-(10x+2x)=3621x-12x=36
9x=36x=4,2x=8
So these two numbers are 84 and 48
-
Let the tens be: x
Then x * 10 + 2x + 36 = (2x)*10 + x12x +36 = 21x
9x = 36
x = 4 gives the number 1 = 48 and the number 2 = 84
-
What grade are you?
It's that simple
If the ten digits are x, then the single digit is 2x
So the original number is 10x+2x
After modulation, it is 10*2x+x
So (10*2x+x)-(10x+2x)=3621x-12x=36
9x=36x=4,2x=8
So these two numbers are 84 and 48
Thank you ·· Give me a few points!
-
Let the single digit be 2x and the ten digit be x
10x+2x)-(20x+x)=-36
x=4 so these two numbers are 48 and 84
-
Let the ten digits be x, then the single digit is 2x, and the question is: (2x*10+x)-(x*10+2x) 36
x=4 2x=8 i.e. the original number is 48
-
Let this number be (ab).
Then according to the condition b=2a
10a+b)-(10b+a)=36
Solving these two equations gives us a=4 b=8
So 48 84
-
In the first problem, first substitute x=-2 into the equation (k-2)*-2=-2-1 solution -2k+4=-3
2k=-7k=The second problem can be solved according to the meaning of the equation 8x-7+6-2x=0, and the solution is 6x=1
x=1 6, the third question, x=-3 2, substituting into the equation, can get 4(-3 2-3a) = 1-7a solution, -6-12a=1-7a
I don't know how to add -5a=7 a=-7 5
-
Solution: There are x rabbits.
4x+2(23-x)=62
2x+46 =62
2x =62-46
x=16÷2
x=823-8=15.
A: There are 15 chickens and 8 rabbits.
-
1. Chickens and rabbits in the same cage. There are 23 heads with 62 legs. How many rabbits are there? (Solve with equations) set rabbits x only.
4x+2(23-x)=62
4x+46-2x=62
2x=16x=8
-
If the chicken is x, the rabbit is 23-x
According to the title (because there are 2 chicken legs and 4 rabbit legs).
2x+4(23-x)=62
x=15A: 15 chickens and 8 rabbits.
-
A car travels at a speed of 40 kilometers per hour from A to B, and after driving for 3 hours, the average speed is forced to decrease by 10 kilometers per hour due to rain, and the result is that it arrives at B 45 minutes later than expected.
Solution: Because of the rain, the average speed was forced to decrease by 10 kilometers per hour, and as a result, it was 45 minutes later than expected.
That is, 45 minutes = 3 4 hours, which is equivalent to 40 3 4 = 30 (kilometers) less
30 10 = 3 (hours) That is, the average speed is forced to decrease by 10 kilometers per hour due to rain, and the time it takes to travel the distance.
Therefore, the distance between A and B is 40 3 + (40-10) 3 = 120 + 90 = 210 (km).
Solve with equations: Solution: Let the estimated time be x. According to the inscription column.
40x=40×3+(40-10)×(x-3+3/4)
40x=120+30x-90+90/4
10x=210/4
x=21/4
That is, the distance between A and B is 40 21 4 = 210 (km).
A: The distance between A and B is 210 km.
-
The distance between A and B is S km.
s/40 = 3+ (s-40*3)/(40-10)-45/60s/40=3+
s=120+1200s-16000-30
1199s=15910
s=15910/1199
-
This kind of problem is still an equation. It takes x hours to reach location B under normal conditions.
Then the distance between the two = 40x = 40x3 + 30 (x + 45 minutes is the hour.)
If we get 10x=, then 40x=210 is the distance between the two.
-
If x mothers have lost 2 children, then there are (40-x) mothers who have lost 1 child.
You can list equations:
2x+(40-x)=70
x=30, so there are 30 mothers who have lost two children.
-
1.Solution: Let the side door pass x people per minute on average, and the main door can pass x + 40 people 2 (x + 40 + x) = 400
2(2x+40)=400
2x+40=200
2x=160
x=80x+40=80+40=120
A: 120 people can pass through the main gate and 80 people can pass through the side door every minute2Solution: It takes x minutes to pass through.
120×2+80)*(1-20%)x=45*4*6256x=1080
x=so comply with safety regulations.
-
Set up the main gate to pass x students per minute, you can get x+x-40=200, and solve x=120
Therefore, the main gate can pass 120 students per minute, the side gate can pass 80 students per minute, 3 doors can pass 120 + 120 + 80 = 320 students per minute, after the efficiency is reduced, it can pass 320 * (1-20%) = 256 students per minute, and 5 minutes can pass 256 * 5 = 1280 students.
The total number of students is 45*6*4=1080
So it meets safety regulations.
-
How many students can pass through one front gate and one side gate per minute?
Set up the main gate is divided into x people per minute, and the side gate y people have:
2(x+y)=400:
x-y=40;
x=120, y=80;
In an emergency, due to the crowding of students, the efficiency of going out is reduced by 20% x = , y = 5 (2x+y) = 1280 students in the whole building at most: 4 6 45 1080 people do not comply with safety regulations, because 1280 1080 means that all can leave in the worst case.
-
(1) Set up a side door to pass x students per minute.
2x+2(x+40)=400
The solution is x=80 x+40=120
So 120 people pass through the main gate every minute, and 80 people pass through the side gate every minute.
2) Number of students = 4 * 6 * 45 = 1080 students.
5 (80 + 120 * 2) * (1-20%) = 1280 1080 so in line with safety regulations.
-
There is one main gate every minute that can pass through x students.
x+(x-40)】*2=400
x = 120 people – per minute at the main entrance.
120-40 = 80 people – side door per minute.
The maximum capacity of the whole building is 45*4*6=1080 people.
Evacuation in 5 minutes in case of emergency:
120*2+80)*(1-20%)*5=1280 people More than 1080, so it meets safety regulations.
1) Set the speed of the water flow to be x m min
80/(10-x)=(100-80)/x >>>More
Petri dishes with diabetics.
Diabetic patients have a blood sugar higher than any time. Western medicine is called sweet polyuria, and Chinese medicine is called thirst, which is emaciation plus polydipsia. Glucose enters the urine. >>>More
Because (2-a) +a +b+c+|c+8|=0 so a = 2, c = -8, a + b + c = 0 >>>More
The actual length of the runway is x meters.
From the title: (x-1):(x-2)=x:( >>>More
Solution: Copper oxide x is required for copper extraction. >>>More