Vision 4.0 is equal to how many degrees, please

Vision 4.0 is equal to how many degrees, please

The uncorrected visual acuity and the power of glasses can't be completely equated. You said that the visual acuity (uncorrected visual acuity) is 4.0 (that is, the original 0.1), which is about 500 degrees of myopia. This is inferred from the empirical formula obtained from our clinical work. The actual power may vary from person to person

The reciprocal of 2 / X is two and a half, and x equals ()
After removing the decimal point of a one digit number, it is 21.6 more than the original number. What is the original decimal? (to calculate the formula) the largest pure decimal composed of three 1's and two 0's is (), and the smallest pure decimal is ()

The reciprocal of two parts of X is x / 2 = 2.5, x = 5
6 / 9 = 24, the original decimal is 2.4
Maximum: 11 / 100, minimum: 1 / 1100