Finding the Fourth Proportional to 39,775.52, 54,890.76 and 21,870.47

Step by Step Solution

1. Step 1: Write the proportion equation
   39,775.52 : 54,890.76 = 21,870.47 : x
2. Step 2: Convert to fraction form
   39,775.52/54,890.76 = 21,870.47/x
3. Step 3: Cross multiply
   39,775.52x = 54,890.76 × 21,870.47
4. Step 4: Simplify right side
   39,775.52x = 1,200,486,939.10
5. Step 5: Solve for x
   x = 1,200,486,939.10/39,775.52
6. Step 6: Final answer
   x = 30,181.55