Finding the Fourth Proportional to 80.73, 111.39 and 53.05

Step by Step Solution

1. Step 1: Write the proportion equation
   80.73 : 111.39 = 53.05 : x
2. Step 2: Convert to fraction form
   80.73/111.39 = 53.05/x
3. Step 3: Cross multiply
   80.73x = 111.39 × 53.05
4. Step 4: Simplify right side
   80.73x = 5,909.24
5. Step 5: Solve for x
   x = 5,909.24/80.73
6. Step 6: Final answer
   x = 73.20