Sixth grade, mathematics, must give praise, to the process

4.X blocks are required to pave the floor with 4 decimeter tiles.

Then 3*112=4*x, i.e., 3 4=x 112 is solved to x=84

Answer. 84 floor tiles of 4 decimeters are required.

6.If the base area is x, the original volume is 6x

From the inscription, 2x=

Solution x = A. The original volume was.

7.If there were x people in class A, there would be (80-x) people in class B.

As the title suggests, x-19 = (80-x) + 19

If the solution is x=59, then 80-59=21

A: Originally, there were 59 people in Class A and 21 people in Class B.

8.Because c=2 r

So r=c2=

s flower bed = r = r + 1 = 5

s=strail=

A: The area of the trail is.

9.Because. So the distance is 3km

It is located xkm away from the Children's Palace

then 8+(x-3)*

x-3)*solution gives x=6

So it is 6km away from the Children's Palace

The other questions are relatively too easy, and you should think for yourself. I'll just answer question 9.

The distance between Li Jun's house and the Children's Palace is x meters.

9+x=12

According to the title, there are:

The radius of the circle r=80 8=10

So the area of the shaded part is:

s = s semicircle - s hollow.

According to the formula for calculating the area of the triangle, the side length of the bottom edge is 20, and then the radius of the semicircle is 10

According to the formula for calculating the area of the circle, the area of the semicircle is 400

80 2 8 equals 20

20 2 equals 10

丌 10 10 is equal to 100 pies.

The bottom of the triangle is 80 2 8, 20, which is the diameter of the semicircle, and then use the formula to set it in.

77 square centimeters... Find out that the radius of the semicircle is 10. The area of the semicircle is 157. Subtract 80 and find it.

It's not 100 it's 50 because it's a semicircle.

Find the area of the semicircle minus the area of the right triangle and the area of the right triangle is shadowed.

Find the area of the semicircle and subtract the area of the triangle.

The Mathematics Q&A team will answer for you, I hope it will be helpful to you.

1. Let the radius of the semicircle r, then 2r = 80, r = 40, and the area of the semicircle = r 2 = 20

Blank area = r 4 + r 2 = 10 + 20 shaded area = parallelogram area + semicircle area - 2 * blank area = 40 square centimeters r * 8 2 = 80, r = 10

Shadow area = semicircle area - blank area = 10 2-80 = 50 -80 77 square centimeters.

I wish you progress in your studies and go to the next level! (

2.Diameter = 24 6 = 4 cm.

3.Area = 7 15-4 (15-4).

61 square centimeters.

2.Let the width of the rectangle be x, 2x+4x=24 x=4cm

3.The top is a square, s=4*4=16 The area of the rectangle below is s=15*(7-4)=45 The total area is s=16+45=61cm.

Question 2, the circumference of the rectangle is 24cm, the two diameters of the circle are equal to the length of the rectangle, and one diameter is equal to the width, so the circumference is the diameter of 6 circles, and 24 divided by 6 is equal to 4cm