What you’ll learn
Find actual lengths from scale drawings.
Key idea
Multiply drawing length by actual meters per drawn centimeter to obtain actual meters.
Drawing centimeters and actual meters are separate; multiply actual-meters-per-drawn-cm forward and divide inversely.
Worked example
Enter the exact value or ordered values in the format requested below.
Scale: 1 drawn cm represents 2 actual meters. A segment is 9cm on the drawing. Enter actual length as a number of meters.
- Every drawn cm corresponds to 2 actual meters.
- Actual length=(9cm)×(2m/cm)=18m; conversely 18m÷(2m/cm)=9cm.
Answer: 18
Quick Check
Evaluate a worked attempt at find actual lengths from scale drawings, identify the first invalid step, and provide the correction.
Scale: 1 drawn cm represents 3m. For a drawn segment of 10cm, Step 1 computes actual length=10/3=10/3m. Locate the first invalid step and correct actual length.