Very simple 1 math problem 5 grades .

Let the side length of the square be x

The surface area of the square is 6*x*x=53

Find x = root number 53 6

v=x*x*x i.e. v=53 6 * root number 53 6 is absolutely correct!

This upstairs should be wrong, you have no reason to give it up.

With 53 6 8 and 5

Because if you want to make a cube, 5 you don't want to give it away.

It is concluded that an area of the cube is 8, the area of the cube is the length of the side, the side length is 8, so the side length is 8, the volume is the base area, the height is 8 8 8 8, the elementary school student should not be able to read the root number, but it should be done.

With 53 6 8 and 5

Because if you want to make a cube, 5 you don't want to give it away.

It is concluded that an area of the cube is 8, the area of the cube is the length of the side, the side length is 8, so the side length is 8, the volume is the base area, the height is 8 8 8 8, the elementary school student should not be able to read the root number, but it should be done.

There is a cube enclosed by 53 square meters of iron sheet, which means that the surface area of the cube is 53 m 2

So the area of a face is 53 6= edge length volume.

There are six sides in total, each side is fifty-three square meters of sixths, and the length of that side is fifty-three sixths of the root number, and the volume is fifty-three times the root number of six minutes is only fifty-three.

The area of each face is 53 6, each edge is (53 6 under the root), and the volume is (53 6) * (53 6 under the root).

root number 53 6). Approximately equal to.

Set the house x meters away from the school, x-120 = 70 (x 90 + 120 90) solves x = 960 meters, (960-120) 70 = 12, so they meet after 12 minutes.

Solution: Suppose the brother and sister meet in x minutes.

90x-70x=120×2

20x=240

x = 12 assuming their home is x meters from the school.

x+120）÷90=（x-120）÷707×（x+120）=9（x-120）

7x+840=9x-1080

2x=840+1080

2x=1920

x=960A: The brother and sister met 12 minutes later, and their home was 960 meters away from the school.

Solution: Let's meet in x minutes.

90x-70x=120*2

20x=240

x=240/20

x=12A: Meet after 12 minutes.

70*12=840 (m).

840 + 120 = 960 (meters).

A: Their home is 960 meters away from the school.

Hopefully).

How does it look like they are ......... 100-meter race

It is easy to see that the brother is 20 meters faster than the younger sister, and the older brother walks 120 2 240 meters more than the younger sister, so the time for the brother and sister to meet is 240 20 12 minutes, and their house is 70 12 120 960 meters from the school.

If you have to use an equation, then if the brother and sister meet after walking for x minutes, then 90x 120 2 70x, the solution is x 12 minutes.

My sister is 120 meters from the school, so the home is 70 12 120 960 meters from the school.

Set the distance to Y meters, meet in x minutes.

Then y=70x+120=90x-120

So: x = 12 minutes.

y = 960 meters.

120*2 (90-70)=12 (minutes).

70*12+120=960 (m).

A: The siblings met 12 minutes later, and their home is 960 meters away from the school.

Let the distance x, equal according to the time: x-120 70 = x + 120 90, x = 960, time 12 minutes.

1.The height of the trapezoid is doubled, and the area is also doubled. (Right).

Area = (top bottom + bottom bottom) * height 2

876060309, hello:

1) When Xiao Ming calculates a decimal division, he treats the divisor as if the result quotient is 3 greater than the correct value. Do you know the correct result for this question?

The divisor is: (Correct result:

2) (Solve with equations) A and B are kilometers apart, and passenger cars and trucks drive out of A and B at the same time, and meet after hours. It is known that the average passenger car travels 65 kilometers per hour, how many kilometers does a truck travel on average per hour?

Solution: Set up trucks to travel an average of x kilometers per hour.

x＋65＝x＝115－65

x＝50

Thinking Training under Grade 5 Mathematics 4

2. The numerator of a simplest fraction is expanded by 4 times, and the denominator is reduced by 3 times to obtain 10, then this simplest fraction is ( ).

3. There are ( ) divisors of 360, and the sum of these divisors is ( ).

4. A mathematics test, the average score of the whole class in May 1st class is 91 points, the average score of boys is 89 points, and the average score of girls is 24 in this class, and there are 24 boys ( ) people, 5. Guangming Bookstore sells a total of 120 books A and B, 5 yuan per book of A and B books.

6. There is a class of students who go rowing, they calculated, if one boat is added, exactly 6 people will sit in each boat, and if one boat is reduced, there will be 9 people in each boat, and there will be a total of ( ) students in this class.

7. Fill in the numbers according to the rules, (

8. A natural number is divided by 3 by 1, 5 by 2, 7 by 3, and 7 by 3, the smallest of this natural number is ( ).

9. If it is known that May 1, 2005 is a Sunday, then October 1 of this year is a week ( ).

10. The length and width of the rectangle are prime numbers, and the circumference is 36 cm, so the area of the rectangle is the largest.

Cm. 11. Xiao Ming walks from home to school, if he walks 60 meters per minute, then he will be 5 minutes late, if he walks 90 meters per minute, then he can be 4 minutes in advance, and the distance from Xiao Ming's home to school is ( ) meters?

12. Xiao Ming has a movie ticket with 10 to 40 rows, the maximum common divisor of the number of rows and seats of this ticket is 13, and the least common multiple is 72.

13. A rectangular timber with a square cross-section, with a surface area of 118 square centimeters, has a surface area of 54 square centimeters after sawing off a maximum cube, and the surface area of the cubic timber sawed is ( ) square centimeters.

15 meters).

5:30-14:00 = 1:30 = hour.

15 divided by kilometers).

Solution: Let these five numbers be , x, (x+2), (x+4), (x-2), (x-4) and the equation gets:

x+x+2+x+4+x-2+x-4=100 is reduced to 5x=100

Solution x=20

The most standard step ha

Even numbers are x-4, x-2, x, x+2, x+4Adding up to 100 gives x=20

Compare sizes:

21 24 is 7 8

Greater than 28 36, 15 18, multiply the numerator and denominator by 2 to get 30 36336 39 is greater than 4 5

Less than 59 60 , 29 30 The numerator and denominator are multiplied by 2 to get 58 60

Write common multiples. Write at least three: common multiples are generally the smallest, right?

Common multiples of 8 and 16: The least common multiple is 16

Common multiple of 3 and none: is it 5? The least common multiple is 15

Common multiples of 18 and 24: The least common multiple is 72

Calculate that two-thirds plus one-half equals seven-sixths, or one-sixths three-quarters plus two-thirds equals seventeenths of twelve, or five-fifths of one-twelfth four-fourths equals thirty-one tenths of twentieths, or one-twentieths eleven-sixths of five-fifths plus four-fifths equals forty-nineties of thirty-nine, or one-thirty-nineteenths two-thirds minus one-half equals one-sixth.

Three-quarters minus two-thirds equals one-twelve.

Four-fifths minus three-quarters equals one-twentieth.

Five sixths minus four fifths equals one-thirtieth.

A day of light rain.

It takes one-third of the whole day for studying, one-eighth of the whole day for cultural and sports activities, and one-twelfth for watching television.

I spent one-twelfth of my meals and three-eighths of my sleep.

1.Less than studying more time a day or sleeping?

One-third is less than three-eighths, so there is more time to sleep.

2.How much more cultural and sports activities than watching TV?

One eighth minus one twelfth equals one twenty-four.

3.How much more sleep than eating?

Three-eighths minus one-twelfth equals seven-fourths.

Less than Less than Less than Less than (didn't understand what you mean) 16 32 64

5 yes) 15 45 90

7/6 17/12 31/20 49/6 1/12 1/20 1/30 9 1 7