How to solve the equation of 1 / 20x + 1 / 25 (300-x) = 13

How to solve the equation of 1 / 20x + 1 / 25 (300-x) = 13

1/20x+1/25(300-x)=13
1/20x+12-1/25x=13
5/100x+12-4/100x=13
1/100x=1
x=100

Time in English (7:15) (5:30) (1:25) (8:55) (6:45)

（7：15） seven fifteen / a quarter past seven（5：30） five thirty / half past five（1：25）one twenty-five / twenty- five past one（8：55） eight fifty- five / five to nine（6：45） six forty- five ...

I don't know anything about equation prime 20% x = 200 45% x = 90 [1-25%] x = 15 30% X-1 / 5 = 5.8
X △ 7 / 8 = 35 / 16 2.5% x-0.5% x = 20 [6x-3] × 1 / 4 = 18
3x out of 10 + 5x out of 7 = 1 out of 60 [5x out of 20-2] = 5
I'm leaving at three

0% x = 200 45% x = 90 [1-25%] x = 15 30% X-5 / 1 = 5.80.3x = 6x = 20x △ 8 / 7 = 35 / 16 x = 16 / 35 × 7 / 8x = 2 / 52.5% x-0.5% x = 20 2.5x-0.5x = 20002x = 2000x = 1000 [6x-3] × 4 / 1 = 186x-3 = 726x = 75X = 12.510 / 3x + 7 / 5x = 60 71 /

30x + (35-x) 25 = 970 how to solve the equation

30X+875-25X=970
30X-25X=970-875
5X=95
X=19

How to solve the equation of 50x = 50 + 30x?

50x-30x=50
20x=50
x=5/2

Damn, who can help me solve the equation? I know the answer is x = 50. But why can't I solve it: 500 / x + 30x / (x + 25) = 30

500/x+30x/(x+25)=30
500(x+25) +30x^2 = 30(x(x+25))
500x + 12500 + 30x^2 = 30x^2 + 750x
12500 = 250x
x = 50

6 / 7 of a number is 10 more than 4 / 5 of 2.5. Find this number. Use the equation solution to calculate the formula

6 / 7 of a number is 10 more than 4 / 5 of 2.5. Find this number. Use the equation solution to calculate the formula
Let this number be X
Lie equation
（6／7）x-10=2.5*（4／5）
(6 / 7) x = 2 × 10
&#The solution is x = 14
Arithmetic
[2.5 * (4 / 5) x 10] / (6 / 7)
=12／（6／7）
=14

One fifth of a number is 60 more than one sixth of a number. What is the number? (equation)

Let this number be x, then we have:
x/5-x/6=60;
x/30=60;
x=1800;
This number is 1800
If you don't understand this question, you can ask,

What number is 1.4 times more than itself 6. Set up equations and find out the solution of the equation

If this number is x, then
1.4x-x=6.4
0.4x=6.4
x=6.4÷0.4
x=16

4.2 times of a number is 2.6 times more than 3.7 times of it

Let the unknowns be a, and the equation be: 4.2a-3.7a = 2.6, then 0.5A = 2.6, so we can solve it, a = 5.2