Ask for help for a junior high school math problem and ask for a solution. I don t know the principl

In the second year, the profit is 50,000 yuan, and then 1 investment, (5 + 5) yuan = 100,000 yuan, this is the second investment, with a cumulative investment of 150,000 yuan;

In the third year, the profit is 150,000 yuan, and the investment continues, (5 + 15) yuan = 200,000 yuan, which is the third investment, with a cumulative investment of 350,000 yuan;

There are only 3 investment opportunities, and I have invested 3 times, and I can't invest again in the future.

Due to the cumulative investment of 350,000 yuan, it will be able to make a profit of 350,000 yuan every year in the future.

100 3 = 97 (years), the total profit in the next 97 years = 97 350,000 yuan = 33.95 million yuan;

The total profit of the 2nd year and the 3rd year = 50,000 yuan + 150,000 yuan = 200,000 yuan;

100 1 = 97 + 2 = 99 (year), total profit in 99 years = 200,000 yuan + 33.95 million yuan = 34.15 million yuan, total principal = 50,000 yuan 3 = 150,000 yuan.

Personal opinion, don't spray if you don't like it!

The first year of investment of 50,000 yuan, this is the first investment;

In the second year, the profit is 50,000 yuan, (50,000 interest + 50,000 wages per year after that) 10,000 yuan = 100,000 yuan, and then accumulated until the 50th year, with a total profit: 50 years - the first year of investment = 49 years x 100,000 = 4.9 million; Then make a second investment;

The second (50 years) investment of 4.9 million + the first investment of 50,000 + 50,000 salary per year after that = 5 million per year after that; After that, it has been accumulated until 75 years, with a total profit of 5 million x 25 years = 125 million, and then the third investment is made;

The third (75 years) investment (125 million + the first two investments of 4.95 million + 50,000 yuan per year after that) x 25 years (the remaining 25 years) = 325000.

In 100 years, three investments plus personal wages totaled 325,000 profits.

Personal comprehension is limited, logical thinking is not very clear, there may be discrepancies, it should be like this, thank you!

Set the cost of A to be $ x and B (500-x) to $.

Analysis: The equivalent relationship is the selling price of A + the selling price of B = the total selling price of A: if it is priced at 50%, it will be (1+50%)x, and if it is discounted, it will be 90% (1+50%)x

B selling price: (the same reason) at 40% price, (1+40%)x, with a 90% discount, it is 90% (1+40%)*500-x).

Total selling price: cost + profit (500 + 157).

90%（1+50%）x + 90%（1+40%）*500-x）=500+157

x=300B: 500-300=200 (yuan).

Answer: The cost of A is 300 yuan, and the cost of B is 200 yuan.

This question is simple to list one yuan once, but it is difficult to have two yuan once) (ask the landlord how many times is the first time?) This is the question of the second year of junior high school, a one-dimensional equation).

The cost of dissolving A x the cost of B y

x+y=500

Solve the system of equations. x=300 y=200

Analysis: Let the costs of A and B be x and y respectively, and list a system of binary equations about x and y. An equation is obtained from the sum of the costs of A and B is 500, and the sum of the profits after 9 folds ** is 157 and another equation is obtained, and the two equations can be solved immediately.

Solution: Let A and B cost x and y respectively, by the system of equations of the title.

Solve the system of equations.

Let the cost of A be x, and the cost of B is 500-x, then the price of A is x+50%, and the price of B is 500-x+(500-x)40%.

The actual pricing is A (x+50%)B (500-x+(500-x)40%)

Column equations. x+50% )500-x+(500-x)40%) solve the equation to find the pricing of x as A... B's is 500-x

A x yuan A pricing (1 + 50%) x = yuan, B pricing (1 + 40%) * 500-x) = yuan.

According to (available.

x = 300 B clothing is 500-300 = 200 yuan.

Junior high school students should learn binary equations.

Cost of A x Cost of B Y

x+y=500

1+50) times 90 x + (1+40) times 90 -x+y) = 157

Simultaneous equations can be calculated by yourself.

If the cost of clothing A is X yuan, the cost of clothing B is 500-X yuan;

Then the price of clothing A is (1+50%)x=yuan, and the price of clothing B is (1+40%)*500-x)=yuan.

then (then x = 300 yuan.

Then B clothing is 500-300 = 200 yuan.

Solution: The cost of clothing for A is x, and the cost of B's is y

Get: x+y=500

y=200 So, the cost of A is 300 yuan, and the cost of B is 200 yuan.

If you have any questions, I will do my best!

If the cost of clothing A is $x, the cost of clothing B is (500-x) yuan.

From the meaning of the title.

If the cost of clothing A is $x, the cost of clothing B is (500-x) yuan.

Only the points E, F are in the middle of Ab, and D will appear in the midpoint of Bf, so ae:af=1:1

Rigorous questioning, this question didn't say that CF is a line segment. Want to ask the question master cf collinear and why.

From the symmetry, H is the midpoint of BF, and FG=EG, DF=AEAF+DF=AD, AF-DF=EF=4, therefore, 2*AF=AD+4....1)

ab=(6/7)*ad

s△abf=2*s△abh=(1/2)*ab*af=(1/2)*(6/7)*ad*af=54...2)

ad*ad+4*ad-4*63=0, i.e., (ad+18)*(ad-14)=0

ad=14, or, ad=-18 (rounded).

ab=12, and, af=9

Let abf= , tan =3 4, and sin =3 5

fh=(1/2)bf=(1/2)*af/sinα=5eg=(1/2)ef/sinα=5/3

Circumference sought = 4 * eg = 20 3

I can't calm down... Freshmen can't read it.

Hehe, even if you ask undergraduates from prestigious universities, you may not be able to do this question, you must ask the teachers and students of the computer department. At present, the controller chapter of "Computer Composition" in colleges and universities does not talk about microprogram control in such detail.

Very simply, using the Peano type we can know that 2 10 = 1024, then the specific format is: , using the Lagrangian formula can be solved to get the word length of 8 bits.

There is no angle in the title.

If 45 and < = angle abc< 90 degrees.

Then take the midpoint E of AB, and then pass E to make the perpendicular line EF of AB inside, connect AF, and BF then the triangle ABF is sought.

If the angle abc is less than 45 degrees.

Draw a circle with ab as the diameter, and connect af and bf to the point f where the circle is inside the graph and the distance from ab is the largest.

Draw the bisector of the angle A with the angle B. The sum of angle A and angle B is 180. Half is 90 degrees. The remaining corner is 90

Take the midpoint E of DC

Lian AE, BE

The triangle ABE is what you want.