How to measure of Ramp surface area

The rate 1:6 generally refers to the ratio of the height of the ramp to the horizontal length of the ramp.

Let x be the tilt angle of the ramp.
Hence, tan x = 1/6
x can be calculated.

The horizontal length of the ramp = 1 m
cos x = 1/ Actual length of the ramp
Knowing the value of x, the actual length of the ramp can be calculated
and the area can be calculated by multiplying the length and the width.