The answer on page 24-26 of the first volume of senior one mathematics, the main process (PEP) 1. -4 2.8 3.- 12 4.-3 5.-3.66.- 1/5 7. 1/65438.
2: 1.3 2.0 3. 1.9 4.- 1/5
3: 1.- 16 2.0 3. 16 4.0 5.-6 6.6 7.-3 1 8. 102 9.- 10.8 10.0.2
4: 1. 1 2. 1/5 3. 1/6 4.- 1
5: 1.3. 1 2.3/4 3.8 4. 13.6
6:9236
7:-5
8:364
9: 169.5
10: It's getting bigger every day.
1 1:-2
12: 1. 16 2.(-3) 3. 18 4.(- 12)5.(-7) 6.7
13:-(∣ negative ∣ * positive)
14:No. 1: 0.5No. 2: 0.3No. 3: 0. 13 Average value: 0.3 1.
People's Education Press, Grade 7 Mathematics Book 16 1 the first 1/page answer1. Average annual household income: (1.3+1.7+2.4+1. 5438+0.5+0.9+3.2+ 1.3+2. 1+2.6+2. 1.0+ 1.8+2.2+ 1.8).
2. Annual income of the whole village:1300,000×1.82 = 2,366,000 yuan = 2,366.6 yuan.
3. 13÷20=0.65=65%
The answer to the second volume of the seventh grade math book is 8.3. The first question:
( 1)3X-Y = 5①(2)2X/3+3Y/4 = 1/5①
5Y- 1=3X+5② 5X/6 -5Y/2=2 ②
Solution: y = 3x-5 ③ From ①; Finishing equations: ①× 12, ②×12;
Substitute ③ into ② to get 8x+9y = 12/5③.
5(3x-5)- 1=3x﹢5 10x-30y = 24④
15x-25- 1 = 3x﹢5 from④:x = 24+30y/ 10⑤。
15x-3x = 5 ﹢ 1 ﹢ 25 Substituting ⑤ into ③ gives:
12X = 3 1 8(24+30Y/ 10)+9 = 2.4
x = 3 1/ 12 192+240y/ 10+9Y = 2.4
Substitute x = 3112 into ① to get: 192+240y+90y = 24.
3×3 1/ 12-y = 5 192-24=﹣240y-90y
7.75-Y=5 168=﹣330Y
7.75-5=Y ﹣28/55=Y ⑥
Substituting σ into σ gives: 10x-30x-28/55 = 24.
10X-﹙﹣840/55﹚=24
10X+840/55=24
10X=24-840/55
X=48/55
Question 2: Solution: Let the average speed of an airplane be X ㎞/m and the wind speed be Y ㎞/m. ..
According to the meaning of the question: 5/2 | x+y | =1200 | 3x+3y =1440 ① used to sort out the equation.
10/3﹙x-y﹚= 1200 4x-4y = 1440②
From ①: x = 480-y ③
Substituting ③ into ② gives: 4 ~ 480-y ~-4y = 1440.
1920-4Y-4Y= 1440
480=8Y
60=Y ④
Substituting ④ into ① gives 3x+3x60 = 1440.
3X= 1440- 180
X=420
A: The average flight speed of an airplane is 420 ㎞/m and the wind speed is 60 ㎞/m. ..
Question 3: Solution: Let the marching speed be X㎞ on the first day and Y㎞ on the second day.
According to the meaning of the question: 4x+5y = 98 ①
4X+2=5Y ②
Get from ①-②: Substitute ③ into ② to get: 48+2 = 5y.
8X=96 50=5Y
X= 13 ③ 10=Y
Question 4: Solution: We use X-ray film as the box body and Y-ray film as the box bottom, which can make the box body and the box bottom just match.
According to the meaning of the question: x+y = 36 ①
25X=40Y÷2 ②
From ①: x = 36-y ③
Substituting ③ into ② gives 25 (36-y) = 20y, and substituting ④ into ① gives X= 16.
900-25Y=20Y
900=45Y
20=Y ④
Answer: Use 16 sheets to make the box, and use 20 sheets to make the box and the bottom of the box just match.
Problem 5: Solution: The cart can transport X tons at a time, and the cart can transport Y tons at a time.
According to the meaning: 2x+3y = 15.5①
5X+6Y=35 ②
From ②-①× 2: x = 4 ③.
Substituting ③ into ① gives 2× 4+3y = 15.5.
3Y= 15.5-8
Y=2.5
3× 4+2.5× 5 = 24.5 tons
A: Three big cars and five small cars can transport 24.5 tons at a time.
Question 6: Solution: Let the slope distance be X and the horizontal distance be Y. ..
According to the meaning of the question: x/3+y/4 = 54/60 ①
Y/4 + X/5=42/60 ②
From ① to ②: 2x/ 15 = 12/60.
2X= 180÷60
X= 1.5 ③
Substituting ③ into ① gives: 1.5/3+Y/4 = 54/60.
Y/4 =54/60 - 1/2
Y/4 =54/60 - 30/60
Y/4=24/60
Y=96÷6
Y= 1.6
1.6+1.5 = 3.1(km)
A: The whole journey from A to B is 3. 1 km.
Problem 7: Solution: Set xkg containing 30% drugs and ykg containing 75% drugs.
According to the meaning of the question: x+y = 18 ①
30%X+75%Y= 18×50% ②
From ①: x = 18-y ③
Substituting ③ into ② gives: 0.3 (18-y)+0.75y = 9.
5.4-0.3Y+0.75Y=9
0.45Y=3.6
Y=8 ④
Substitute ④ into ① to get x = 10.
Answer: You need to take 30% liquid medicine 10kg and 75% liquid medicine (8kg).
Question 8: Solution: Let a commodity use X yuan for each piece and B commodity use Y yuan for each piece.
According to the meaning: 60x+30y = 1080①
50X+ 10Y=840 ②
From ②× 3-①: 90x = 1440.
X= 16 ③
Substituting ③ into ② gives 50× 16+ 10y = 840.
10Y=840-800
Y=4
500× 16+500×4
=8000+2000
= 10000 yuan
10000-9600 = 400 (yuan)
It's cheaper than no discount, 400 yuan.
Question 9: Solution: Set a toothbrush for X yuan and a box of toothpaste for Y yuan.
According to the meaning of the question: 39x+2 1y = 396①.
52X+28Y=5 18 ②
Sort out the equation: 13x+7y = 132.
13+7Y= 129.5
A: This record is wrong, because it is said in the title that it is sold at the same price, and the above equations have no solution, so it is wrong.
(People's Education Press) In the seventh grade, the math book practiced on page 44, and the third question on page 47 didn't use a calculator!
Take 12 points 1X plus 20 points 1X= 1-(20 points 1 times 4) for the answer to the small question on page 23 of the second volume of the seventh grade math book.
The answer to the question on page 154 12 of the seventh grade People's Education Edition Mathematics Book is straight line AC=5CM. Then take a protractor and make an angle ACD= 145 degrees. Find the point B 6CM away from the point C on the straight line AD.
Connect AB. Measure its length with a ruler. Then multiply it by 10 and change the unit to m, which is the actual distance of AB.
The seventh grade people's education edition mathematics book exercises 3.4 answer 3 questions.
Solution: suppose this dress is worth x silver coins, then
(x+ 10)/ 12=(x+2)/7
x=46/5
That is, this dress is worth 46/5 silver coins.
Four questions
Solution: If the price of this commodity is X yuan per piece, then
(x-90%×250)/250= 15.2%
x=263
That is, the price of this commodity is 263 yuan per piece.
The seventh answer (writing process) of P 102, the first volume of Senior One Mathematics Book (People's Education Edition) is: when there is no wind, the speed of the plane is X km/h, and 2 hours and 50 minutes = 17/6 hours.
(X+24)× 17/6=(X—24)×3
The solution is X=840.
Distance: (x-24) × 3 = 2448km.
Answer. . . . . . . . . . . . . . . . . . . . . .
Is it because the process is too urgent and simple that you can't do the 5 7 8 question on page 103 of the second volume of the seventh grade math book? Stupid old man! Is your brain a cow's stomach?
You certainly don't know what a cow's stomach is!
————————— straw bag!
You're done! Still studying, it's a complete waste of money!