A score of 20 for math problems can be increased to 20 in the process

Solution 1Because there is no cover, the entire side and a bottom surface need to be counted, that is, 60 * 40 + (60 * 30 + 40 * 30) * 2 = 8400 square centimeters.

2.(1) In the same way, only the side is counted, that is, (square meters.

2) square meters = 168000 square centimeters.

168000 (30*20)=280 pieces.

8400 (square centimeters).

square meters) to make such a box at least how many planks are used at least square meters.

square meters) the area of wall tiles is square meters.

30cm= 20cm=

280 (blocks) Requires 280 blocks.

1: First convert cm to m because there is no cover, so it is calculated according to 5 faces, so the column formula is: 2 * (square meters 2: < 1> 2 * (square meters <2> first cm to m to get 2 * ( block.

One. Because I don't know which side of the lid is which side, there are three possibilities.

1.60x40x2 + 40x30x2 + 60x30 = 9000 square centimeters.

2.60x40x2 + 60x30x2 + 40x30 = 9600 square centimeters.

3.40x30x2 + 60x30x2 + 60x40 = 8400 square centimeters.

So at least square meters.

2. The total area of the four walls is: square meters.

The area of each wall tile is: square meters.

Divide by the number of tiles required. =280

So at least 280 pieces are needed.

1.Solution: 60x40 + 2x40x30 + 2x60x30 = 8400 square centimeters = square meters.

2..Solution: (1) square meters.

2) 30cm = 20cm = square meters.

Block (divided by).

Forehead. Probably yes.

1.Plank: 60 * 40 + (60 * 30 + 40 * 30) * 2 = 8400 square centimeters.

2.i.e. (sqm.)

square meters = 168,000 square centimeters.

168000 (30*20)=280 pieces.

1. At least the area of wooden planks = the surface area of the wooden box (without cover) = 60 * 40 + (60 * 30 + 40 * 30) * 2 = 8400 square centimeters = square meters.

2. Wall tile area = bathroom side area = (square meters.)

The area of each wall tile = 30 * 20 = 600 square centimeters = square meters.

A wall tile is required.

1.Is there anyone else participating in the class except for the 51 class, no is 1 62Obviously, because the unit "1" is the same, 5 6 7 103

Innumerable, column 61/420, 62/420, 63/420....69/420, 601/4200, 602/2400....699/4200....

Fill in the blanks to score, calculate, divide, and divide.

You're a student, right? It's not good to be lazy in this way. Help you once, not for example.

There were 36 students in the May 1st class who participated in the mathematics expert competition, and 6 of them won the first prize. What percentage of the total number of participants won the first prize? Sixth.

Ming Ming and Xiao Hua read the same storybook respectively, Ming Ming read 5/6 of this book, and Xiao Hua read 7/10 of this book. Which of them sees more?

Why? Five sixths is equal to fifty tenths of sixty, and seven tenths is equal to forty-two tenths of sixty, so it is obvious that there is a lot to see.

Think about it: How many fractions can you write that is smaller than 1/6 and larger than 1/7? Convert it. For example, 13/84, 25-27/168, 49-55/336, and so on.

2/3 of a meter can represent either 1 meter (2/3) or 2 meters (1/3).

Fill a vacancy. The addition and subtraction method of calculating different denominator fractions should pay attention to the first (through the denominator), and then (calculate the addition and subtraction), and the calculation result can be (approximate the denominator).

Obviously because 5 6> 7 10

Countless: 13 84 23 168 24 168 25 168 .

Addition and subtraction of molecules, simplification, simplification.

1.Three giant pandas eat 31 and a third of the orange swim in four days, that is, (94 3) kilograms of bamboo.

Each giant panda eats 94 3 3 = 94 9 kg of bamboo for four days.

Each giant panda eats 94 9 4 = 47 18 kg of bamboo per day.

Five giant pandas eat 47 18 x 5 = 235 18 kg of bamboo per day.

Five giant pandas eat 235 18 x 6 = 235 3 kg of bamboo for six days.

Can be connected 94 3 3 4x5x6 = 235 3 3 and three-fifths (18 5) = 15

300 x 15 = 4500 Round Pins are required.

1. Two-fifths of the way through the whole journey is still 10 meters away from the midpoint, so.

2 5 is 1 2-2 5 = 1 10 from half

So 1 10 is 10 meters, the whole journey is 100 meters, and 100 2 5 = 400 meters.

2. When the speed of the fast train is 80 km/h, the speed of the slow train is 80 (4 3)=60 km/h.

The two cars travel opposite each other, and the speed is 80 + 60 = 140

After driving for 3 hours, went 140 3 = 420

The two cars are still 2 5 away from each other, that is, the two cars are gone, the 3 5 of the whole journey is 420, and the whole journey is 420 (3 5) = 2100 3 = 700 kilometers.

3. Number A = Number B + 40

The number B is less than the number of A 1 5, and the number B = the number of A - 1 then the number of 5 A = 4 5 The number of A.

Number A = Number B + 40 = 4 5 Number A + 40

1 5 A number = 40

A number of clear marks and = 200

1.Let the whole journey be x meters, then 2 5 * x + 10 = 1 2 * x solve the equation trembling beam x = 100, so the line is 2 5 * 100 = 40 meters, convert the unit, kilometers (the estimated unit is problematic).

2.Set the total length of A and B x kilometers, the two cars are still 2 5x kilometers apart after 3 hours of driving, the fast train key Shen 3 hours 3 * 80 = 240 kilometers, the slow car 3 * 80 * 3 4 = 180 kilometers, so 240 + 180 + 2 5x = x

Solve the equation, x=700

3.Let the number A be x and B be y, then x-y=40, x-y=1 5x, substitute the solution equation, x=200, y=160

Solution: 1, mn=mc+cn=(1 2)ac+(1 2)cb=(1 2)ab=8 2=4

m is 1 8 of the whole country, so the per capita resource share of the country is 300 (1 8) = 2400m

is 1 32 of the world, so the per capita resource share of the world is 300 (1 32) = 9600m

2) The amount of water loss caused by one year is at least 6*a*10 5+2*b*10 5 m

3) Let the standard water consumption be x, then the amount of water exceeding the standard in this month is 12-x, then the equation can be known.

x=8 Therefore, Beijing stipulates that the monthly guaranteed water consumption of a three-person building is 8m

Huyan Jue Luo Yu Xiujie, hello:

1.Zhongbai warehousing sales in the first quarter of this year is 2.7 million yuan, the sales in the second quarter increased by two percent compared with the first quarter, how many yuan is the sales in the second quarter?

270 (1, 20%) 324 (10,000 yuan).

2.During the eleventh period, the books in Xinhua Bookstore were all 85% off, why 15 yuan a book for 100,000 books, and how many yuan for 20 books and 100,000 books?

15 85% 20 255 (yuan).

3.To build a 2,500-meter-long road, Team A repaired 40% of the total length, and Team B repaired 36% of the total length.

Question 1; How many meters did Team A repair? 2500 40% 1000 (m).

Question 2; How many meters did Team B repair? 2500 36% 900 (m).

Question 3; How many meters does Team A repair more than Team B? 2500 (40%, 36%) 100 (m).

Question 4; How many meters are left unrepaired? 2500 (1, 40%, 36%), 600 (m).

4.The original price of a book is 80 yuan, with a 25% increase, how much is the current price?

80 (1, 25%) 100 (RMB).

5.A book is 240 pages, 20% of which have been read, how many pages have not been read?

240 (1, 20%) 192 (pages).

1.An increase of 20 percent is a multiple of 2.7 million, and the answer is 2.7 million * 4 million....80*

means multiplied.

270+270*20%

There is something wrong with the second question, a 15 yuan, 20 books is 20 * 15, but I don't know if this 15 has been discounted or not, the question is not clear.

Three: Team A 2500*40% Team B 2500*36% Team A is better than Team B 2500*40%-2500*36% Left: 2500*(1-40%-36%) meters.

Four: 80* (1+25%)

Five: 240 (1-20%)

3.Armor. 2500 B. 2500 A repairs 1000-900=100 more than B

2500-(1000+900)=600 left

1.When the two cars meet, the time taken is the same, the distance ratio is 5:3, so the speed ratio is also 5:3, and the speed of the truck is 36km h, so the speed of the passenger car is 36 * 5 3 = 60km h, and the distance is 6 * 60 = 360km

2.Let the speed of car A be v1 and the speed of car B be v2, and the system of equations can be obtained from the problem: 14v1=14v2+140, 8(v1+v2)=14v1 can be solved v1=40, v2=30, so ab is 14v1=560km apart

1.It takes 6 hours for a passenger car to travel from A to B, and the truck travels 36 kilometers per hour, and now the passenger car and the truck travel in the opposite direction from A and B respectively, and the ratio of the distance traveled by the passenger car and the truck when they meet is 5:3. Find out how many kilometers apart A and B are between them.

Solution: Let A and B be separated by x kilometers.

x/6:36=5:3

x = 360 km.

2.Two cars, A and B, traveled in the same direction from A and B at the same time, and met in 8 hours. After the encounter, the two cars continued to move at the original speed, and after 6 hours, car A arrived at place B, car B was still 140 kilometers away from place A, how many kilometers are the two places apart?

Solution: Let ab and the two places be separated by x kilometers, and x 8 represents the sum of the two velocities x 8*6+140=x

x = 560 km.

Columnar calculations. One number is 1 out of 6 and the other is 15 out of 12, what is their sum?

The sum of two years old with a handicap plus is 17/18. One of the additions is 4/9, and what is the other addition?

Subtracting 7/9 of a number results in 5/18. What is this number?

5 18 + 7 9 = 19 18 = 1 and 1 18