The sum of 4.5 times of Y and 0.5 times of Y is 20? The product of 20 and 5 is 99 times more than 10 times of X. how much is x? There are 365 pear trees and peach trees in the orchard. The number of peach trees is more than twice that of pear trees. How many pear trees and peach trees are there in the orchard? Fifth graders subscribe to 360 magazines, 60 less than three times the number of fourth graders. How many magazines do the two grades subscribe to? Party A and Party B have 90 science and technology books in total, and Party A's book is 3.5 times of that of Party B. how many science and technology books do Party A and Party B have? A has 82 more stamps than B, and a has three times as many as B. how many stamps does a and B have? The sum of divisor, divisor, quotient and remainder is 57, where quotient and remainder are 8 and 2 respectively. What is the divisor? Don't be wrong when you answer

The sum of 4.5 times of Y and 0.5 times of Y is 20? The product of 20 and 5 is 99 times more than 10 times of X. how much is x? There are 365 pear trees and peach trees in the orchard. The number of peach trees is more than twice that of pear trees. How many pear trees and peach trees are there in the orchard? Fifth graders subscribe to 360 magazines, 60 less than three times the number of fourth graders. How many magazines do the two grades subscribe to? Party A and Party B have 90 science and technology books in total, and Party A's book is 3.5 times of that of Party B. how many science and technology books do Party A and Party B have? A has 82 more stamps than B, and a has three times as many as B. how many stamps does a and B have? The sum of divisor, divisor, quotient and remainder is 57, where quotient and remainder are 8 and 2 respectively. What is the divisor? Don't be wrong when you answer

1. Y is 4
2. X is 0.1
3. There are 120 pear trees and 240 peach trees
4.500 copies
5. There are 20 copies in B and 70 copies in a
6. There are 41 in B and 123 in a
7. There is an equation for this
Let the divisor be X. then the divisor is (57-8-2-x)
x+2+8+（57-8-2-x)=57
I can't tell you all about it, or it's meaningless, right? Isn't it/

The first problem is to use the equation,
1. In order to facilitate wheelchair access for the disabled, a city passed a regulation on the height of the front slope of buildings
For every 0.1M high slope, a horizontal length of at least 1.2m is required. Now there is only 18m long open space in front of a building, so how many M can the maximum slope be designed here
2. In a country, the number of male athletes is more than 3 / 5 of the total number, and the number of female athletes accounts for 1 / 3 of the total number?

1. According to the meaning of the title, the ratio of the horizontal length to the height of the slope is certain, so it is in a positive proportion
If the slope is set here, it can be designed up to x meters
1.2／0.1=18／x
1.2x=0.1×18
x=1.8÷1.2
x=1.5
2. The total number of athletes participating in the Olympic Games is one,
Unit one is unknown, so the corresponding quantity △ corresponds to the fraction = unit one
Then; 5 △ [1 - (3 / 5 + 1 / 3)]
=5÷[1－14／15]
=5÷1／15
=75 (person)
I hope my answer can help you!

And related knowledge about equations

1. Number of copies × number of copies = total number
Total number of copies
Total number of copies = number of copies
2.1 times × times = several times
How many times △ 1 times = Times
Several times △ times = 1 times
3 speed × time = distance
Distance △ speed = time
Distance △ time = speed
4 unit price × quantity = total price
Total price / unit price = quantity
Total price △ quantity = unit price
5. Working efficiency × working time = total amount of work
Total workload △ work efficiency = working hours
Total amount of work △ working time = working efficiency
6 addend + addend = sum
Sum - one addend = another addend
7 subtracted - subtracted = difference
Subtracted difference = subtracted
Difference + subtraction = subtracted
8 factor × factor = product
Product △ one factor = another factor
9 divisor / divisor = quotient
Divisor / quotient = divisor
Quotient x divisor = divisor
Primary school mathematics figure calculation formula
1 square
C perimeter s area a side length
Perimeter = side length × 4
C=4a
Area = side length × side length
S=a×a
2 cube
5: Volume a: edge length
Surface area = edge length × edge length × 6
S table = a × a × 6
Volume = edge length × edge length × edge length
V=a×a×a
3 rectangle
C perimeter s area a side length
Perimeter = (length + width) × 2
C=2(a+b)
Area = length × width
S=ab
4 cuboid
5: Volume s: Area A: length B: width H: height
(1) Surface area (L × W + L × H + W × h) × 2
S=2(ab+ah+bh)
(2) Volume = length × width × height
V=abh
5 triangles
S area a bottom h height
Area = bottom × height △ 2
s=ah÷2
Triangle height = area × 2 △ bottom
Triangle bottom = area × 2 △ height
6 parallelogram
S area a bottom h height
Area = bottom × height
s=ah
7 trapezoid
S area a upper bottom B lower bottom h height
Area = (upper bottom + lower bottom) × height △ 2
s=(a+b)× h÷2
8 round
S area C perimeter Π d = diameter r = radius
(1) Perimeter = diameter ×Π = 2 ×Π× radius
C=∏d=2∏r
(2) Area = radius × radius ×Π
9 cylinder
v: Volume H: height s; bottom area R: bottom radius C: bottom perimeter
(1) Side area = perimeter of bottom surface × height
(2) Surface area = side area + bottom area × 2
(3) Volume = bottom area × height
(4) Volume = side area △ 2 × radius
10 cone
v: Volume H: height s; bottom area R: bottom radius
Volume = bottom area × height △ 3
Total number △ total number of copies = average number
The formula of sum difference problem
(sum + difference) △ 2 = large number
(sum difference) △ 2 = decimal
The problem of sum times
Sum (multiple-1) = decimal
Decimals × multiples = large numbers
(or sum - decimal = large)
Differential multiple problem
Difference (multiple-1) = decimal
Decimals × multiples = large numbers
(or decimal + difference = large)
The problem of tree planting
1. The tree planting problem on non closed lines can be divided into the following three cases
(1) if trees are to be planted at both ends of the non closed line, then:
Number of plants = number of segments + 1 = total length △ plant spacing-1
Total length = plant spacing × (number of plants - 1)
Plant spacing = total length (number of plants - 1)
(2) if trees are to be planted at one end of the non closed line and not at the other end, then:
Number of plants = number of segments = total length △ plant spacing
Total length = plant spacing × number of plants
Plant spacing = total length △ number of plants
(3) if trees are not planted at both ends of the non closed line, then:
Number of plants = number of segments-1 = total length △ spacing-1
Total length = plant spacing × (number of plants + 1)
Plant spacing = total length (number of plants + 1)
2. The quantitative relationship of tree planting on closed lines is as follows
Number of plants = number of segments = total length △ plant spacing
Total length = plant spacing × number of plants
Plant spacing = total length △ number of plants
Profit and loss
(profit + loss) △ the difference between the two distributions = the number of shares participating in the distribution
(big profit - small profit) △ the difference between the two distributions = the number of shares participating in the distribution
(big loss - small loss) △ the difference between the two distributions = the number of shares participating in the distribution
Encounter problem
Encounter distance = speed and X encounter time
Encounter time = encounter distance △ speed and
Speed sum = encounter distance △ encounter time
Follow up questions
Pursuit distance = speed difference × pursuit time
Pursuit time = pursuit distance △ speed difference
Speed difference = pursuit distance △ pursuit time
Flow problem
Downstream velocity = hydrostatic velocity + water velocity
Countercurrent velocity = still water velocity - water velocity
Hydrostatic velocity = (downstream velocity + countercurrent velocity) △ 2
Water flow velocity = (downstream velocity countercurrent velocity) △ 2
Concentration problem
Weight of solute + weight of solvent = weight of solution
Weight of solute / weight of solution × 100% = concentration
Weight of solution × concentration = weight of solute
Weight of solute △ concentration = weight of solution
Profit and discount
Profit = selling price cost
Profit margin = profit / cost × 100% = (selling price / cost-1) × 100%
Up and down amount = principal × up and down percentage
Discount = actual selling price △ original selling price × 100% (discount < 1)
Interest = principal × interest rate × time
After tax interest = principal × interest rate × time × (1-20%)