Area of Each wall = Length * Height
Area of Ceiling = Length * Width
Area of Floor = Length * Width
Area of Window = Height of Window * Width of Window
Area of Trapezoid = Height * (b1ð+b2) _ð 2
Area of Triangle = Base * Height * .5
Number of gal. of Paint = Total Area to be Painted _ð 400 Sq. Ft./Gal.
Ratio of Window to floor area = Window Area _ð Floor Area
Volume = Length * Width * Height
Volume = Length * Width * Depth
Cubic Yds. = Cubic Ft. * 1 Cubic Yd. _ð 27 Cubic Ft.
Echoes time for round trip is T= D/C , D is distance between boards and C is sound velocity (1100 ft/s)
Frequency = C/D = 1000/D
Reverberation Time (RT) The reverberation time in a room at a given frequency is the time required for the mean-square sound pressure in that room to decay from a steady state value by 60dB after the sound suddenly ceases. This is one of the most vital, though not the only, measures of a rooms acoustic properties and can be a guide to the suitability of a room for a given purpose.
Where RT = Reverberation Time (s), V = room volume (feet^3), S = total surface area of room (feet^2), µð = the average absorption coefficient (dimensionless)
RT = 0.05 * V _ð (µð * S), (see Deaf Architects & Blind Acousticians?)