Three math problems Hurry up, I m in a hurry!

1) The minimum is a multiple of 3 12 (3*4) and the maximum is 99 (3*33) so yes.

2) The least common multiple of 12 and 16 + 1 is OK is 49 people.

Divisible by 2 is an even number, with 50.

divisible by 3 is (1*3=3 33*3=99)(33-1)+1=33.

Divisible by 5 is (1*5=5 20*5=100) (20-1)+1=20.

Plus some of them are duplicates.

2,3 repeats have 2*3=6 (1*6=6 16*6=96) 16.

2,5 repeats have 2*5=10 (1*10=10 10*10=100)10.

3,5 repeats have 3*5=15 (1*15=15 6*15=90) 6.

Subtract some plus duplicate 2*3*5=30 (1*30=30 3*30=90)3.

The answer is 100-50-33-20+16+10+6-3=26 (verified by exhaustive method).

4) Even numbers are assumed to be 2n equation (2n-2 + 2n +2n+2)=294 and n= 49 3 even numbers are.

2n-2= 96 2n=98 2n+2=100

5) Odd numbers: Suppose the middle number is 2n+1 equation (2n+1-2+2n+1)-(2n+1+2)=89 and the solution is n=46 and the 3 odd numbers are.

2n+1-2=91 2n+1=93 2n+1+2=95

2).The least common multiple of 12,16 is 48, so there are 48+1=49 people.

3).1-100 is divisible by 2 x , 1 = < 2a< = 100, a has x = 50; There are y divisible by 3, 1=<3b<=100, and b has y=33; There are z divisible by 5, 1=<5c<=100, and c has z=20; There are m divisible by 2 and 3, 1=<2*3d<=100, and d has m=16; There are n divisible by 2 and 5, 1=<2*5e<=100, so that e has n=10; There are p divisible by 3 and 5, 1 < = 3 * 5 f< = 100, and f has p = 6; divisible by 2, 3 and 5 is q 1< = 2 * 3 * 5 g < = 100, and g has q = 4; That is, w=100-(x+y+z-m-n-p+q)=25.

1. Sum is still a multiple of 3, (3+6+9+......99）

people, 12*4=48, 16*4=48

3. It is to find the prime number, which is divisible by 5 and 20. 10 divisible by 2, 3 divisible by 3, and 7 remaining.

1. There are respectively

The least common multiple of 16 is 48, and because there is 1 more person, there are 49 people in this class.

3. There are respectively

i.e. 26 pcs).

1.The difference series is 12+ ......99＝3x37x30/22.Subtracting 1 person is a multiple of 12 and 16, and the least common multiple is:

48.Add 1 more for 493The numbers that are divisible by one of them are:

That's 28 left.

1 100 11 and 1/5 20 7 100 56 5 20 7 68 yuan.

2 After-tax interest of 2000 yuan.

3 50 (1 3 10) 35 kg 35 (1 2 7) 25 kg.

III 1 ＝15/14×7/10×9/8=27/322．＝3＋4/6-7/6

4 1 12 points: 36 points: 4 points.

2 solution 1 2 1 4 2 5

7 17 1 10000000 = 170000000 cm = 1700 km.

8 25% of 2008 is 80% of 502 2510 is 200810 With a "20% discount" ** batch of goods, that is, according to the original price of 8 percent, that is, according to the original price of 80% **.

11 Practice 50 shots in a row, 8 misses, the hit rate is 84% 12, if 7x=8y, then x:y=8:7:;

1 100 11 and 1/5 20 7 100 56 5 20 7 68 yuan.

2 After-tax interest of 2000 yuan.

3 50 (1 3 10) 35 kg 35 (1 2 7) 25 kg.

III 1 ＝15/14×7/10×9/8=27/322．＝3＋4/6-7/6

4 1 12 points: 36 points: 4 points.

2 solution 1 2 1 4 2 5

7 1700 km.

25% of 8 2008 is 80% of 502 2510 is 80% of 200810 **, at 80% of the original price**.

12. If 7x=8y, then x:y=8:7:;

1.100-11 and 1/5 20 7 = 68 (yuan) Answer: Fruit merchants should find Xiao Wang 68 yuan.

2.2000 yuan).

150 (1-5%)=RMB).

Answer: The after-tax interest is RMB, and the after-tax principal and interest are RMB.

3.(1-3 10) 2 7=1 550 (1-3 10-1 5)=25 (kg) Answer: There are 25 kg left in this barrel of oil.

III 11 and 1/14*

2.Another 1/6

IV. 1Simplification ratio: 36 minutes: 240 seconds.

Solution: Hour = 12 minutes, 240 seconds = 4 minutes.

Hours: 36 minutes: 240 seconds = 12:36:4 = 3:9:12) Knowing that 1/2:5 = 1:1:x of 4, find the solution of the value of x: 1 2:2 5=1 4:x

x=1 57, there is a map of China with a scale of 1 10000000, and the map measures from Shanghai to Beijing.

The distance is 17 centimeters, so the actual distance from Shanghai to Beijing is 17,000 kilometers.

8. 25% of 2008 is 502, and 80% of 2510 is 2008.

10. A batch of goods with "80% off" is 80% of the original price, that is, 80% of the original price.

11. Practice 50 shots in a row when shooting, 8 shots missed, and the hit rate is 16% 12. If 7x=8y, then x:y= 8:7;

1.100-20 7 56 5 = 68 yuan 22000 yuan; The principal is 2000 yuan, and the principal and interest are 2150 yuan.

3.50 (1-3 10) = 35 kg; 35 (1-2 7) = 25 kg.

3 15 14 7 10 9 8=27 32 11 4+2 3+1 4-7 6=

4:1) 3:9:1

The question is not difficult, I hope you will do it yourself next time, and you will be responsible for yourself, not necessarily all right.

These questions are too simple, do it yourself, help you do it, it is a trap for you.

Dear, press the calculator yourself.

Do you have time to type, but don't have time to do the questions? It's time to finish the fight. I do my homework and sleep a little more every day.

Don't waste everyone's time on this kind of topic, okay

1. All set the waist length to B, and the bottom edge length to A

Then 15-9 = b-a

15+9=2b+a

Get b = 10a = 4

In two cases, the conclusion can be obtained by assigning that the waist length is 2x and the bottom edge is y, 3x=9, x+y=15 or 3x=15, x+y=9.

The waist length is 5 (in the first case, it is not possible to form a triangle), and the bottom length is 4.

Waist length A Bottom length B

3 2 a=9,1 2a+b=15 to launch a=6,b=12 (2a-b=0, unreasonable aversion).

1 2a+b=9,3 2 a=15 out, a=10,b=4

Set the waist length x, the bottom edge y

x+x/2=15

x/2+y=9

then x=10, y=4

or x+x 2=9

x/2+y=15

then x=6, y=12

At this time, 6+6=12, the sum of the two sides is not greater than the third side, and it is not true.

Let the waist length a and the bottom edge length b, there are two possibilities: (1) a + a 2 = 9, b + a 2 = 15, the solution a = 6, b = 12However, 6+6=12 is not true.

2) a+a 2=15, b+a 2=9, the solution is a=10, b=4, and it is verified by testing. Waist length 10cm, bottom length 4cm

1. Fill in the blanks.

1.The formula for calculating the area of triangles and trapezoids with letters is (ah 2) and ((a+b)h 2)).

2. 230 ) dm2 3200cm2=( 32 )dm2

2500 ) cm2 6500 m² = (hectares.

3.The base and height of a parallelogram are both (, and the area of a triangle of equal height is (

4.The two right-angled sides of a right-angled triangle are and respectively, and the hypotenuse is long, and the area of this right-angled triangle is (

5.The area of a triangle is 240 m2, the height is 40 m, and the base is (12) m.

6.Two identical trapezoids can be put together into one (parallelogram).

7.If the circumference of a square is 32 dm, then its side length is (8) dm and its area is (64) dm2.

8.The area of a parallelogram is 36 m2, and if you reduce its base and height to 3 times, the area of the parallelogram is (4 m2).

9.If the upper bottom of a trapezoid is enlarged by 2 times, and the lower bottom is also expanded by 2 times, and the height remains the same, then its area is expanded by (2) times.

10.Design a triangle with an area of 24 square meters, with a base of (12 meters) and a height of (4 meters).

2. True/False questions.

1.The area of the triangle is equal to half of the parallelogram. （x）

2.The circumference of the two gardens is equal, and they must also be equal in size. （x）

3.The base of a triangle is enlarged by 2 times, and its area is also expanded by 2 times with the same height. （√

4.Two triangles with the same base and height are not necessarily the same shape, but they must be equal in area. （√

5.Two trapezoidal pieces of paper of equal size must be able to form a parallelogram. （x）

3. Multiple choice questions.

1.The area of a flat quadrilateral is 2 cm high and the base is (a)cm.

a. b. c. 2 d.

2.The school basketball court covers an area of about.

a.hectares bsquare meters cm dsquare kilometers.

3.What can be put together into a rectangle are two identical (d) triangles.

a.Acute angle bIsosceles cBlunt angle dRight angle.

4.The area of the trapezoid is known to be 45dm2, the upper base is 4dm, the lower base is 6dm, and its height is (a)dm.

a. 9 b. c. d. 45

5.The circumference of an isosceles trapezoid is 48 cm, the area is 96 square centimeters, and the height is 8 cm, then the waist length (b).

centimeter centimeter centimeter centimeter.

Triangular area = bottom height 2 trapezoidal area = upper bottom + lower bottom height 2 square meters = 65 hectares.

The base and height of a parallelogram are (square meters), and the area of a triangle of equal base and height is (

The two right-angled sides of a right-angled triangle are and the hypotenuse is long, and the area of this right-angled triangle is (the area of a triangle is 240m, the height is 40m, and the base is (12)m.

Two identical trapezoids can be put together into one (rectangle).

If the circumference of a square is 32 dm, then its side length is (8) dm and its area is (64) dm2.

Triangular: s= ah trapezoidal: s= (a+b)h2 23 ) dm

3200cm=( 320 )dm

25 )cm

6500 square meters = (hectares.

3.The base and height of a parallelogram are both (, and the area of a triangle of equal height is (

4.The two right-angled sides of a right-angled triangle are and the hypotenuse is long, and the area of this right-angled triangle is (cm).

5.The area of a triangle is 240m, the height is 40m, and the base is (12)m6Two identical trapezoids can be put together into one (parallelogram).

7.The circumference of a square is 32dm, then its side length is (8)dm, and the area is (64)dm

Children, just elementary school, just starting to learn, can you use snacks?