How to solve the equation x-0.18x = 32.8

How to solve the equation x-0.18x = 32.8

x-0.18x=32.8
(1-0.18)x=32.8
0.82x=32.8
x=32.8÷0.82
x=40

2 / 5x divided by 1 / 4 = 5 / 6 18x-2.5x = 3.1

2 / 5x divided by 1 / 4 = 5 / 6
2/5X=4*5/6
2/5X=10/3
X=(10/3)*(5/2)
X=25/3
18X-2.5X=3.1
15.5X=3.1
X=3.1/15.5
X=0.2

4×（5.5x＋x）=78

4×（5.5x＋x）=78
5.5x+x=78÷4
6.5x=19.5
x=19.5÷6.5
x=3

How far is a light year?

30 * 365 * 24 * 3600 = 946080 million km

Round______ The ratio of is called PI

The ratio of circumference to diameter of a circle is called PI

(radical three minus radical two) &?

Original formula = square of root 3 bracket - 2 × root 3 × root 2 + square of root 2 bracket
=3-2 × radical 6 + 2
=5-2 times the root 6

Given LG2 = 0.3010, find LG25

lg25=lg(5^2)=2lg(5)=2lg(10/2)=2(lg(10)-lg(2))=2(1-lg2)=1.398

Note: if a is an integer, then the cubic minus a of a can be divided by 6
If there is a process, why can three consecutive natural numbers be divisible by 6?

There is at least one even number among three continuous natural numbers, and only one number is a multiple of 3, so the multiplication of three continuous natural numbers can be divisible by 2 and 3 at the same time, that is, divisible by 6

Given that the elliptic equation x2 / 9 + Y2 / 25 = 1, the point P (1,1) is the midpoint of the chord ab of the ellipse, find the linear equation where AB is

Let the coordinates of two points AB be (x1, Y1) (X2, Y2)
(x1)2/9+(y1)2/25=1 .1
(x2)2/9+(y2)2/25=1.2
Point P (1,1) is the midpoint of the chord ab of the ellipse
（X1+X2）/2=1 .3
(Y1+Y2)/2=1.4
From Formula 1 to formula 2, we can get the following formula: 1
（X1-X2）（X1+X2）/9 +（Y1-Y2）（Y1+Y2）/25=0
By substituting formula 3 and 4 into the above formula, we can get: (y1-y2) / (x1-x2) = - 25 / 9, which is the slope of the straight line ab. we also know P (1,1), and we can get the equation of the straight line AB from the point oblique formula, which is 9y + 25x-34 = 0

The difference between the two prime numbers is 2. What are the two prime numbers?
Urgent. Urgent

Within 100:
3、5
5、7
11、13
17、19
29、31
41、43
59、61
71、73