The product of the difference between 8 and a certain number multiplied by 2 is 1. How much is this number? (solve the equation)

The product of the difference between 8 and a certain number multiplied by 2 is 1. How much is this number? (solve the equation)

Let this number be X
Countable equation
（8-X）*2=1
The solution is x = 7.5

A number plus the sum of 8 times 2, the product is 287, what is the number? (solved by equation)

Let this number be x, (x + 8) × 2 = 287 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X + 8 = 143.5, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 135.5. A: this number is 135.5

The number a is 20, 6 times the number a is less than 5 times the number B, what is the number B?