Heavy bounty for elementary school math problems, bounty for math problems

1.1026 (54+60)=9 minutes Calculate the time it takes for two people to meet from the beginning, that is, the time it takes for the dog to run, and then use this time * the dog's speed to know how many meters 70*9=630 meters.

2.First calculate the circumference of the fish pond (60+30)*2=180 meters, and then use the perimeter to remove the distance between them to know how many trees are 180 3=60.

Because you don't have to think what kind of tree it is, if you want it, it's 56 willows and 4 poplars (just 4 horns).

2) As long as it is divisible by 30 and 60 and is greater than 3 meters, it meets the requirements, but it cannot be greater than 15, because there must be 4 willow trees, 5, 6, 10, 15.

1 1026 (54+60)*70=630 meters Just calculate how many minutes the dog has been running.

2 (60+30)*2 3=60 trees Perimeter spacing = number of trees.

It is more appropriate to change to 6 meters, which can be divisible by 30 and 60, and greater than 3.

1026 (54+60)=9 minutes.

70*9=630 meters.

A total of 2 * 21 + 2 * 11-4 = 60 (including 56 willows, 4 poplars) if transplanted, as little as possible to move the trees, so 3 m * 2 6 m is more appropriate.

Question 1: The time it takes for the two to meet is the time it takes for the puppies to run together, so the puppies run together:

70 1026 (54 60) 630 meters.

Question 2: 1) A total of planting:

60 30) 2 3 60 trees.

2) It is more appropriate to change the spacing of the trees to 6 meters.

1. Just consider the time it takes for the dog to run.

1026 (54+60)=9 minutes.

70*9=630 meters.

A total of 2*(19+9)+4=60 trees are planted (including 56 willows and 4 poplars) The second question is not any specific requirements?

Change to 5 meters or 6 meters.

Percentage of boys meeting the standard = 60%.

A total of 49 goals were thrown.

The Wolf Hunter team will answer for you.

Number of qualified people: 6 (with a score greater than or equal to 0).

Percentage of compliance: 6 10 100% = 60%.

6 people to score: 5 6 + (1 + 0 + 0 + 3 + 2 + 1) = 37 goals, 10 people to score: 10 5 + (1-1 + 0-2 - 3 + 3 + 2 + 1-2) = 49 goals.

Solution: Analysis: Record Grades" = 0 then meet the standard, and the number of students who meet the standard is 6, so 6 10 = 60%, that is, the percentage of male students who meet the standard is 60%;

Taking 5 as the standard, 5*10=50, and recording the number of more than 5 and less than 5, then 1+(-1)+0+(-2)+(3)+0+3+2+1+(-2)=-1

Then 50 + (-1) = 49, i.e. they have made a total of 49.

Hello, the beauty of mathematics has you covered.

A negative number means less than five, which means failing! There are six that are greater than or equal to zero, so there are 6 10 that meet the standard

A total of 5*10 (1-1 0-2-3 0 3 2 1-2 ) 49

Attainment rate: 6 10 100% = 60%.

5 10 + 1-1-2-3 + 3 + 2 + 1-2 = 49 (pcs) Answer: The percentage of these 10 boys who met the standard was 60%, and they scored a total of 49 goals.

Hello landlord, take a look at my answer!

6 divided by 10 times 100% = 60%.

A total of 6+4+5+3+2+5+8+7+6+3=49 were thrown.

Look at how many positive numbers there are, that is, how many meet the standards: there are 6 in total.

That is, the compliance rate is 6 10 * 100% = 60%.

A total of (1-1+0-2-3+0+3+3+2+1-2)+10*5=49.

The attainment rate is divided by the number of non-negative numbers divided by the total number of people 6 10*100%=60% A total of 49 goals were thrown.

The percentage was 6 10, out of a total of 49.

In fact, the area of the shaded part is the area of the triangle

2×4=8（cm）8×4÷2=32÷2=16（cm²）

A: The area of the shaded part is 16 square centimeters.

Solution: The area of the parallelogram is a r 2r=2r 2 quarter circle area b r 2 4

Triangle area c 1 2 r 2 shadow area a-b-c+(b-c).

a-b-c+b-c=a-2c

2r 2-r 2=r 2=4 4 = 16 square centimeters, and the shaded part has an area of 16 square centimeters.

s=1/2*4^2=8cm2.Move the right shadow to the left, and the two shadows will become a triangle.

The base of the parallelogram is equal to the diameter of the semicircle, which is 4*2=8 cm, and the radius of the parallelogram, which is 4 cm.

Slice the shadow next to the parallelogram into it, see figure for the method.

Therefore, the area of the shaded part is 8*8 2=16 square centimeters.

Answer: (n 3-3n 2-7n+37) is a natural number then n 3-3n 2-7n+37=k 2 is a perfect square number, n 3-3n 2-7n+37-k 2=0

It belongs to the ternary linear equation, which can be solved by applying the Shengjin formula.

Requirements: n is an integer, k is a natural number.

The first process is 28 people.

The second process is 42 people.

The third process is 48 people.

Clause. The speed ratio of the first, second and third processes per hour is: 48:32:28=12:8:7

It is required that the number of parts in the three processes of Wencheng is the same every day, and the number is set.

The first, second, and third courses are arranged in order for x, y, and z people.

Then: 12x=8y=7z, i.e. y=3 2x, z=12 7x.

If there are 118 people, then: x+y+z=118. i.e. x+3 2x+12 7x=118

Solution: x=28, y=42, z=48i.e. the first.

The first, second and third processes should be arranged.

Solution: Set the number of workers in the first process as A

Workers in the first process complete parts per day: 48x24, workers in the second process complete parts per day: 32x24, workers in the third process complete parts per day: 28x24, workers in the first process complete parts per day: workers in the second process complete parts per day = (48x24):(32x24) = 3:2

Workers in the first process complete parts per day: Workers in the third process complete parts per day = (48x24):(28x24) = 12:7

That is: the number of parts completed by the workers of the second process per day is 2 3 of the number of parts completed by the workers of the first process per day, and the number of parts completed by the workers of the third process per day is 7 12 of the number of parts completed by the workers of the first process per day

The total number of parts completed per day in each process = the number of workers x the number of parts completed by each worker per day.

The total number of workers completed in each process is the same every day, so the number of workers is inversely proportional to the number of parts completed by each worker per day, that is: the number of workers in the second process is 3 2 of the number of workers in the first process, and the number of workers in the third process is 12 7 of the number of workers in the first process

Then: a+(3 2)a+(12 7)a=118, the solution is: a=28, (3 2)a=42, (12 7)a=48

Therefore: 28 workers are arranged for the first process, 42 workers are arranged for the second process, and 48 workers are arranged for the first process.

In order to make each process do not produce backlog or shutdown and other materials, the parts book completed by the three processes per hour is the same, and the first process needs at least x people, the second process needs at least y people, and the third process needs at least z people, then 48x=32y=28z, that is, find their least common multiple.

48x=32y=28z, that is, 4*12*x=4*8*y=4*7*z, the least common divisor is 4, and the least common multiple is 12*8*7=672

x=672/48=14,y=672/32=21,z=672/28=24.

That is, the first process needs at least 14 people, the second process needs at least 21 people, and the third process needs at least 24 people to be suitable.

The least common multiple of the first is 693, so that you can know that when three processes complete 693 parts at the same time every day, these three processes should be arranged with people respectively, equal to 236 people, exactly 2 times that of 118 people, so the correct answer should be: each process should be arranged with people.

Ratio of the number of people in the three processes:

1 48:1 32:1 28 14:21:24 First Process Arrangement:

118 14 (14 21 24) 28 (person) Second process arrangement:

118 21 (14 21 24) 42 (person) Third process arrangement:

The ergonomic ratio of the three is as follows:

The first way: the second way: the third way = 1 48:1 32:1 28 = 14:21:24, 14 + 21 + 24 = 59

To make the number of parts completed in each process the same, the first process: 118 times 14 59 = 28.

The second process: 118 times 21 59 = 42.

The third process: 118 times 24 59 = 48.

Set to x y z, 48x=32y=28z, and x y z=118, respectively, so we get x:y:z=14:

Set up x, y, z respectively

then 48x=32y=28z

x+y+z=118

48x=32y, y=3x2

48x=28z, and z=12x 7

i.e. x+3x 2+12x 7=118

Solution: x=28, y=42, z=48

It is recommended that such topics be removed from primary school textbooks.