Third, CADCACCDCC

4. 1,1800x5+2500 =11500 (kg) =1/0.5t.

1 1.5 tons < 12 tons

You can pass

2.0.2x2000=4000 (cm) = 40m.

40/3≈ 13 (layer)

3.8X610 = 480 (cubic centimeter) =480ml

The volume of the same object is smaller than the volume, so it is false.

4. 500 x (30/10) x10 =15000ml =15l.

Page 47

1. 1，5x 200/y s-7 9n？ d？

2. Equation 4

Equation 2 3 7 9

3. Angle 3 =180-90-x = 90-x.

Angle 3= 180 degrees -2x degrees

Angle 3=( 180 degrees-ideal degree) /2=90 degrees-1/2x degrees.

4 、( 4)+x= 13

x-(6.7)= 2.3

(0. 1)xx=0.9

x/(9/5)=5

5. 1.5b+2.5 5.5

6、x-2 x+2

7、x/y 1/y

8、 23 8

Second, x to x to x to x.

Three solutions equation: x-4/5 = 1/3.

x=5/3

X/2/3x9/ 10=3

x=20/9

10x 0.36—25% = 1. 1

x= 10

4, 1, 2/9x=52

x(2/9+2/5)= 138

(2/5—2/9)x=30

2 、( 80+60)x+ 12=30

3. Solution: Set a ***x page.

X (1-1/3) = 30 or1/3 = x-30.

All by hand, I hope to adopt it.