Rounding numbers
Writing functions:
round(x, n)
Rounds a number x. if the fractional part is less than 0.5 then rounding is less, more, and in the majority
The number of n - shows how the numbers to make the rounding, such as
round(1234.443, 2) = 1234.44
round(1234.443, 4) = 1234.443
round(1234.443, 0) = 1234
round(1234.443, -2) = 1200
round(1234.443, -4) = 0