It is sometimes impractical to make engineering drawings full size. If the part to be drawn is…

It is sometimes impractical to make engineering drawings full size. If the part to be drawn is very large or small, a scale drawing is generally made. The scale, which is shown on the drawing, compares the lengths of the lines on the drawing to the dimensions on the part. A scale on a drawing that states  means the drawing is one-quarter the size of the part. It is expressed as a ratio of 1 : 4 or  . A scale drawing that states 2” 5 1” means that the drawing is double the size of the part. It is expressed as a ratio of 2 : 1 or  . The actual dimensions of a steel support are given in Figure 20-11. All dimensions are in inches. Using the proportion given, compute the lengths for each unknown in the table. Round the answers to 3 decimal places where necessary.