A master of math is advanced, and two sixth grade math problems are asking for help

1. Side area = square meters.

Meta is required. 2. Bottom circumference = decimeters.

Base radius = decimeters.

1 base area = square decimeter.

Total base area = 2 square decimeters.

Square decimeter = square meter.

Square metre. Yuan.

1. Find the surface area.

Analysis: If you combine a cylinder, you will get a rectangle (the base area is not considered at this time, because there is no need to paint), as long as the unit is uniform, it can be calculated according to the area of the rectangle.

s = square meters.

80* yuan. 2. The side area is the area of the rectangle mentioned above, so the perimeter of the bottom area is decimeters.

The radius of the base area is r=c (2*)=dm.

Base area = r 2 = square decimeters.

1.Decimeter = meter multiplied by 10 = square meter multiplied by 6 times 80 = multiplied by 80 = yuan).

Solution: Set the original x grams of water in the cup.

1-5/9)[(1-1/3)x+40]=240(4/9)[(2/3)x+40] =240(2/3)x+40=240*(9/4)

2/3)x=540-40

x=500*(3/2)

x = 750 A: There are 750 grams of water in the cup.

Solution: Set the cup to have x grams of water.

1/3x+(1-1/3x)*5/9+240=x+40x=675

The answer is that the cup turned out to have 675 grams of water.

Let the total x, there is 2 3 x left after the first pour, 2 3 x+40 after rewinding, and 4 9 * (2 3 x+40) = 240 after the second pour

2/3 x+40=540

x = 750 grams.

Suppose there are x grams of water in the cup.

2 3x+40)*(1-5 9)=240 to get x=

So there are grams of water in the original cup.

If there is x grams of water in the cup, then:

2x/3）+40]*(4/9)=240

The solution is x=750 (grams).

The first step is to find out how much water is after pouring 1 3 and then 40 grams?

240 4 9 = 540 grams.

How many grams of water are in the bottle before pouring 40 grams of water?

540-40 = 500 grams.

This 500 grams of water is the weight of 2 3 in the bottle, and the weight of the original water in the bottle can be found.

500 2 3 = 750 grams.

Solution: Set the original water x grams.

x-three-molecule one x+40-nine-fifths * (x-three-molecule one) = 240

Suppose there is x grams of water in the cup, and the formula can be listed from the title: x-[(1-1 3)x+40]*(5 9)=240, and the solution is x=7080 17

Suppose the speed of the original passenger car and the van was 4x, 5x, and the total distance at the time of meeting was Y hours.

The speed of the bus after lifting the limb = x * (reed parsley 1 + 20%) = because the bus traveled a total of 4x * y = 4 * 5x before the meeting

So y=5x

So ab two places are separated = 4*5x+4*

Therefore, AB two places are separated by calendar base = 4x*y + 5x*y = 45xx = 20, so AB two places are separated = 900 meters.

Let the distance be s, the passenger car is 4x, and the truck is 5x, then the truck went 5s 9 when disturbing the congratulatory encounter, and the passenger slow circle sent the car to go 4s 9, and then, the root cavity is equal in time, 4s 9 5x=(5s 9-115) 4x(1+20%), and the two sides are about x at the same time, and the solution is, s=25875 29

The speed of the original passenger car ride is 4x, 5x, and the total travel time is Y hours.

The speed of the bus = x * (1 + 20%) = because the bus traveled 4x * y = 4 * 5x before the meeting

So y=5x

So ab two places are separated = 4*5x+4*

Therefore, AB is 2 places apart = 4x*y + 5x * y = 45xx = 20, so AB 2 places are separated = 900 meters.

If you still don't understand, you can click on the username to me** to ask questions, and I will do my best for you.

1.The fraction subtracts 6 from the numerator and denominator, and obtains 3 5 after the fraction, indicating that the sum of the numerator and denominator before the original fraction is equal to 100-6-6 = 88, and now the sum of the numerator and denominator of 3 5 is (3 + 5) = 8, so the sum of the numerator and denominator before the fraction should be (3 * 11) (5 * 11) = 33 55, so the original fraction is (33 + 6) (55 + 6) = 39 61

2.When 40 students were doing 3 math problems, 25 of them got the first question right, 28 of them got the second question right, and 31 of them got the third question right

1) The person who does both the first question and the second question correctly is 25 + 28-40 = 132) The person who does both the first question and the third question correctly is 25 + 31-40 = 163) The person who gets both the second question and the third question right is 28 + 31-40 = 19, so the person who gets all three questions right is 13 + 16 + 19-40 = 4 Remarks: The question of 2 seems to be a bit problematic, the question says that there are 31 people who do the third question correctly, but the question is at least how many people do the third question correctly, Do you want to ask the number of people who do the three questions correctly?

1) Set the distance xm

x = 160 3 km.

160 3 km apart.

2) Set up x washing machines and 3x color TVs.

3x-x/10*15=120

Explanation: x 10 indicates how many days the washing machine was sold out, and multiplied by 15 indicates how many color TVs were sold during those days.

3x represents the number of color stations, and if you subtract the ones sold, you will be left with 120 units.

3/2x=120 x=80

There are 80 washing machines and 240 color TVs.

The distance between the two cities is (13+3) (80%-50%)=16 30%=160 3 km.

2.Set up a shopping mall to ship x washing machines, then the number of color TVs is 3x.

The time taken for the washing machine to be sold out is x 10, so the color TV sold during this time is 15*x 10=units.

Then 3x = so the solution is x=80, then 3x=240

So the mall shipped 80 washing machines and 240 color TVs.

Question 1: Let the whole journey be s, after four hours, A travels 3 kilometers more than B, then A travels S 2+13+3, which is 80% of the whole journey, then the whole journey is: (s 2+13+3) 80%=s, you can find s=kilometers.

Question 2: There are x washing machines and y color TVs, and the number of color TVs is 3 times that of washing machines: y=3x;

After the washing machine is sold out, there are 120 color TVs left: y-x=3x-x=2x=120, x=60 can be found, that is, 60 washing machines, then the color TV is60x3=180.

According to the meaning of the title, it can be listed, and the first floor is the correct solution, so I won't repeat it.

Let the whole process be as follows: A is gone, B is gone, s=160 3

Solution: Let the distance of ab be x kilometers.

80%x÷4-3=（1/2x+13）÷4

x=250/3

Binary one-time don't understand and then ask.

y=3xy-（x/1o）15=120

x=80 y=240

1. If the distance is S, then the driving distance of car A is and the driving distance of car B is the subject of the title:

2,I don't know if you have learned the binary equations,If you don't learn,Then set up a washing machine x set,The number of color TVs is 3x。

Time is invariant. Since the washing machine is sold out, it can be counted as time t=x 10. From the perspective of color TV, t=(3x-120) 15

So: x 10 = (3x-120) 15, the solution is x = 8

Understand the meaning of the question carefully:

1.The canteen burns 200 kg more coal in March than in April, and 30% less in April than in March, that is to say, the 30% saved in April is exactly 200kg compared with March, and the coal used in March is 200 (30%) = 2000 3kg2In the first half of the month, 45% of the whole process was repaired, and 55% of the whole process was repaired in the second half of the month, and the second half of the month was 200m more than the first half of the month, which is 55%-45%=10% of the whole process, so the whole process is 200 (10%)=2000m

Divide by 30% 2200 divided by 45% You see if what I wrote is correct.