1. Solution: We assume that the oil inventories of the two factories are equal after X days.
126- 12x=94-8x
126- 12x+8x=94
126-4x=94
4x=32
x=8
Answer: After 8 days, the stocks of the two factories are equal.
2. The ratio of the number of parts planned to be produced by Party A and Party B last month is 4:5. As a result, Party A completed more than 15%, and Party B still had 2% of the plan unfinished, so they * * * produced 1 7 10 parts. What was their production target planned last month?
Solution: Let part of planned production be part X.
2. Solution: Let a part of planned production be X pieces.
( 1+ 15%)4x+( 1-2%)5x = 17 10
1. 15 * 4x+0.98 * 5x = 17 10
4.6x+4.9x= 17 10
9.5x= 17 10
x= 180
A: 180*4=720 pieces B: 180*5=900 pieces.
A: The production target of plan A is 720 pieces, and the production target of plan B is 900 pieces.
3. The sum of two numbers of a two-digit number is 13, and the number of the tenth digit is twice less than that of the single digit.
3. solution: let the ten digits be X.
x+(2x-2)= 13
3x-2= 13
3x= 15
x=5
2*5-2=8
A: This two-digit number is 58.
A stall owner sold a customer two pieces of clothes at the price of 48 yuan. The stall owner said that one of them earned 20% and the other lost 20%. The client says you don't make a profit or lose money. This client, right? What's your opinion?
No, it's a loss
48/( 1+20%)=40 yuan
48/( 1-20%)=60 yuan
40+60= 100 Yuan
48+48=96 yuan
100-96 = 4 yuan
A: I lost 4 yuan.
5. To transport 29.5 tons of coal, transport it three times by a truck with a load of 4 tons, and transport the rest by a truck with a load of 2.5 tons. How many times will it take to complete?
It takes x times to complete.
29.5-3 * 4 = 2.5 times
17.5=2.5x
x=7
Seven more shipments are needed to complete.
6. The trapezoidal site covers an area of 90 square meters, with an upper bottom of 7 meters and a lower bottom of 1 1 meter. How high is it?
Its height is x meters.
x(7+ 1 1)=90*2
18x= 180
x= 10
Its height is 10 meter.
A workshop plans to produce 5480 parts in April. It has been in production for 9 days, and 908 more are about to complete the production plan. How many pieces will be produced on average every day in these 9 days?
During these 9 days, X was produced every day on average.
9x+908=5408
9x=4500
x=500
During these nine days, an average of 500 were produced every day.
8. Two cars, Party A and Party B, are driving in opposite directions from two places 272km apart. Three hours later, the distance between the two cars is still 17km. A travels 45 kilometers per hour, and B travels how many kilometers per hour?
B travels x kilometers per hour.
3(45+x)+ 17=272
3(45+x)=255
45+x=85
x=40
B is driving at a speed of 40 kilometers per hour.
9. Two classes in grade six in a school scored an average of 85 points in mathematics last semester. There are 40 students in six classes (1) with an average score of 87. 1. There are 42 students in Class Six (2). What is the average score?
The average score is X.
40*87. 1+42x=85*82
3484+42x=6970
42x=3486
x=83
The average score is 83 points.
10, the school bought 10 boxes of chalk, and used 250 boxes, leaving 550 boxes. How many boxes per box on average?
Average x boxes per box
10x=250+550
10x=800
x=80
80 boxes per box on average.
1 1 and 4 * * 200 students. Extracurricular activities, 80 girls go skipping rope. The boys are divided into five groups to play football. How many people are in each group?
There are x people in each group on average.
5x+80=200
5x= 160
x=32
There are 32 people in each group on average.
12 The canteen delivered150kg of rice, which was 30kg less than the flour delivered. How many kilograms of flour does the canteen send?
The canteen brought x kilograms of flour.
3x-30= 150
3x= 180
x=60
The canteen brought 60 kilograms of flour.
13. There are 52 peach trees and 6 rows of pear trees in the orchard. There are 20 more pear trees than peach trees. How many pear trees are there in each row on average?
There are x pear trees per row on average.
6x-52=20
6x=72
x= 12
There are 12 pear trees in each row on average.
14. The area of a triangular piece of land is 840 square meters, the bottom is 140 meters, and the height is how many meters?
The height is x meters.
140x=840*2
140x= 1680
x= 12
The height is12m.
15, Li Shifu bought 72 meters of cloth and just made 20 adult clothes and 16 children's clothes. Adult dresses are 2.4 meters each, and how many meters are children's dresses?
Each piece of children's clothing is made of x meters.
16x+20*2.4=72
16x=72-48
16x=24
x= 1.5
Each piece of children's clothing1.5m.
16, three years ago, my mother was six times older than my daughter. This year, my mother is 33 years old. How old is my daughter?
My daughter is x years old this year.
30=6(x-3)
6x- 18=30
6x=48
x=8
My daughter is 8 years old this year.
17. How long will it take for a car with a speed of 50 kilometers per hour to catch up with a car with a speed of 40 kilometers per hour that left two hours ago?
It takes x time
50x=40x+80
10x=80
x=8
It takes eight hours.
18, Xiaodong bought 3 Jin of apples and 2 Jin of pears at the fruit shop, and paid 15 yuan. 1kg apples are more expensive than 1kg pears in 0.5 yuan. How much are apples and pears per kilogram?
Apple x
3x+2(x-0.5)= 15
5x= 16
x=3.2
Apple: 3.2
Pear: 2.7
19, A and B start from A and B at the same time, respectively, in opposite directions. A travels at a speed of 50 kilometers per hour, and B travels at a speed of 40 kilometers per hour. A reaches the midpoint 1 hour earlier than B. How many hours does it take for A to reach the midpoint?
X hours to reach the midpoint.
50x=40(x+ 1)
10x=40
x=4
A reaches the midpoint in 4 hours.
20. Party A and Party B set out from A and B at the same time and met face to face for 2 hours. If A starts from place A and B goes in the same direction at the same time, then A will catch up with B after 4 hours. Given that the speed of A is 15km/, find the speed of B. ..
Speed x of b
2(x+ 15)+4x=60
2x+30+4x=60
6x=30
x=5
B's speed 5
2 1. Two ropes with the same length, the first one was cut15m, and the second one was 3m more than the first one. How long are these two ropes?
It turns out that these two ropes are each x meters long.
3(x- 15)+3=x
3x-45+3=x
2x=42
x=2 1
It turns out that the two ropes are each 2 1 m long.
22. A school bought seven basketballs and 10 soccer balls and paid 248 yuan. As we all know, the price of each basketball is equivalent to the price of three footballs. How much is basketball and football each?
Every basketball x
7x+ 10x/3=248
2 1x+ 10x=744
3 1x=744
x=24
Each basketball: 24
Each football: 8