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Anonymous users2024-02-051.The water fee is 128 yuan》40*(
That is, more than 40 tons of water are used.
Set water x tons of water Partial cost not exceeded: 40 * ( Excess partial cost (not more than part of the cost + more than part of the cost = total cost.)
x = 60 tons.
2. The first piece is profitable (60 125%) * 25% = 12 yuan.
The second loss (60 75%) * 25% = 20 yuan.
So it's a loss of 8 yuan.
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Anonymous users2024-02-041. Solution: X tons of water were used.
Because 128>62
So, more than 40 tons of water are used.
62+（x-40）*
Solution x = 35 with 35 tons of water.
2. Solution: Let one piece be x and the other piece y, then:
1+25%)*x=60 x=48 60-48=12 Earn 12 yuan 1-25%)*y=60 y=80 80-60=20 Lose 20 yuan.
To sum up: a loss of 8 yuan...
The landlord remembers to give points!
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Anonymous users2024-02-0320+40 = 60 tons.
If you lose money, you will sell it for 60 and you will make a profit and a loss, and the cost of the one will be relatively high, and the loss of 25% will be relatively more.
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Anonymous users2024-02-02Solution: Let p(x,y),pf1|²/|pf2|²=[(x+c)²+y²]/[(x-c)²+y²]=1+[4cx/(x²+c²-2cx+y²)]
p(x,y) satisfies the analytic formula of the circle (x-5c 4) +y =9c 16, which is simplified.
x²+y²+c²=5cx/2 ……
Substitute for |pf1|²/|pf2|²=9
pf1/pf2=3
2) Let the elliptic equation be x a +y b =1(a>b>0), because q point is also on the ellipse, so qf1 qf2=3 is known from the conclusion of the previous question
From the definition of the ellipse, qf1+qf2=2a, the above two equations are solved together to obtain qf1=3a 2, qf2=a 2, in f1qf2, f1f2=2c, which is obtained by the cosine theorem.
f1f2 = qf1 +qf2 -2*qf1*qf2*cos f1qf2, ie.
2c) = (3a 2) +a 2) -2 * (3a 2) * (a 2) * 3 5), simplified to C a = 2 5, so, eccentricity e = c a = (2 5) = 10 5.
3) Because o is the midpoint of the line segment F1F2, Qo is the midline of F1QF2, which is owned by the midline theorem.
qf1 +qf2 =2oq +2of2, ie.
3a 2) +a 2) =2*( 34 2) +2c, combined with c a= 10 5 obtained from the previous question, the two equations are solved consistennly.
a = 10, c = 2, and then the solution is b = 6, so the equation for the ellipse is x 10 + y 6 = 1.
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Anonymous users2024-02-01Nine-sixteenths by c squared, I'm exhausted!!
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Anonymous users2024-01-311. (182 + 178 + 176) 2 = 268 C jump 268-182 = 86 cm.
A jump 268-178 = 90 cm.
B jump 268-176 = 92 cm.
There are 20 male workers 3 + 5 = 65 people.
There are 20 female workers.
Xiaohong has 210 3 = 40 = 590 yuan.
Xiao Ming has 210 yuan.
There were 6 sunny days and 5 rainy days.
5. From the 1st floor to the 11th floor, a total of 11-1=10 stairs A person from the 1st floor to the 11th floor has to walk a total of 17 10=170 steps (1+3+3 5)=10
The number C is 10, the number B is 30, and the number A is 150
There are a total of 154 flowers to sell.
8. Dongdong lives on the 3rd floor, and goes home on 2 floors of stairs, the first floor is 46 2 = 23 steps, and it is clear that he lives on the 7th floor and goes home on 6 stairs, a total of 23 6 = 138 steps.
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Anonymous users2024-01-301 A, B and C practice high jump, A and B jump a total of 182 cm, B and C a total of 178 cm, A and C a total of 176 cm, how many centimeters do the three people jump each?
A: (182+178+176) 2-178=90
B: (182+178+176) 2-176=92
C: (182+178+176) 2-182=86
2 There are 85 workers in one workshop. There are 3 times more male workers than female workers, how many male and female workers are there in this workshop?
Female: (85-5) (3+1)=20;Male: 85-20=65
3 Xiaohong and Xiao Ming have a total of 800 yuan for the New Year, and Xiaohong is 3 times less than Xiao Ming, 40 less. How much do they cost?
Xiao Ming: (800+40) (3+1)=210, Xiao Hong: 800-210=590
4 The People's Liberation Army (PLA) conducted camping exercises, walking 35 kilometers a day on sunny days, 28 kilometers on rainy days, and a total of 350 kilometers in 11 days.
Rainy days: (35*11-350) (35-28)=5;Sunny: 11-5=6
5 How many steps does a person have to walk from the first floor to the 11th floor of a building with 17 floors and 17 steps on two adjacent floors?
6 The sum of the three numbers A, B, and C is 190, the number A is 5 times the number B, and the number B is 3 times that of C.
C: 190 (1+3+3*5)=10, A: 10*3*5=150
7 Zhenzhen sells flowers on the roadside, Xiao Zhang bought half of all the flowers and 3 less, Xiao Li bought half of the remaining flowers and 5 less, and the remaining 45 flowers were not sold, so how many flowers did Zhenzhen have to sell?
After Xiao Zhang buys flowers, before Xiao Li buys flowers, there are really flowers: (45-5)*2=80
Before Xiao Zhang buys flowers, that is, the real original: (80-3)*2=154
8 Dongdong obviously lives in the same building, Dongdong lives on the 3rd floor, and it takes 46 steps to go home, and how many steps do you have to go home when you live on the 7th floor?
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Anonymous users2024-01-291 Let A x, B y, C z x+y=182, y+z=178, y+z=176 to get A90 B92 C86
2 Female workers x people, x+3x-5=85x=20 65 males and 20 females.
3 Let Xiao Ming's x yuan, x+3x-40=800Solution x=210 Xiao Ming 210 yuan, Xiao Hong 590 yuan.
4 Set x sunny days, 35x+28(11-x)=350, and solve x=6 6.
6 Let C x, 15x+3x+x=190, and the solution is x=10, so A is 150
7 has a flower x 1 2x-3 + 1 2 (1 2x+3)-5=x-45, and the solution is x=154
8 46 divided by 2 equals 23, 23 * 6 = 138 138
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Anonymous users2024-01-281.A + B = 182 a
B + C = 178 b
A + C = 176 C
a-c = b-c = 6 d
b + d = 2 B = 184 B = 92 C = 86 A = 902Let female workers = x male workers = 3x + 5
x+3x+5=85 x=20 male=65
3.Set Xiao Ming x Xiao Hong 3X-40
x+3x-40=800 x=210 Xiaohong5904Set sunny day x
35*x+（11-x）*28=350
x=65.（11-1）*17=170
6.Let C x B 3 x A 15x
x+3x+15x=190
x=10 A150
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Anonymous users2024-01-271'38% it contains (38
1%2' There are 50 students in the class, of which only 1 person failed the exam, and the pass rate is (98)%3 'Realistic Elementary School Week 1 to the school 792 students, the absenteeism rate is 1%, the whole school has a total of (800
Person. 4'The price of a down jacket after a 20% discount is 120 yuan, and the price before the discount is (150) yuan?
What is 5'8 minus 25% of 18 to get a 100-fold wider? (There is a process) (8-18*25%)*100=(
6'4/5 of A is equal to 40% of B, B is 250, what is A?
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Anonymous users2024-01-26Calculate the volume of the cube = then the volume of the hole, and first calculate the radius of the hole r=1 2. The volume of the hole v=(r2)*1. If the cube has 6 faces, the volume of the 6 holes is 6*( r 2)*1.
The remaining volume = the volume of the cube - the volume of all holes =
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Anonymous users2024-01-25If two straight lines (k is not equal to 0) are perpendicular, then these two lines and one of the horizontal or vertical axes can always form a right triangle, and the two inner angles of the right triangle that are not at right angles are tana tanb = 1, so if a straight line slopes at one of the inner angles of the triangle, then the slope of the other line perpendicular to it is the slope of the outer angle of the other corner of the right triangle, so tana (-tanb) = -1.
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Anonymous users2024-01-24Well, this should be right, there are a lot of them on the Internet.
Let L1 be perpendicular to L2, the inclination angle of L1 is a, the slope is k1, the inclination angle of L2 is b, and the slope is k2, you may wish to set a>b
Because L1 is perpendicular to L2
So a=b+90
tana=tan(b+90)=cot(90-(b+90))=-cotb
And because tana=k1, tanb=k2
So k1*k2=tana*tanb=-cotb*tanb=-1over.
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