Finding the Fourth Proportional to 72,173.72, 99,595.69 and 39,906.47

Step by Step Solution

1. Step 1: Write the proportion equation
   72,173.72 : 99,595.69 = 39,906.47 : x
2. Step 2: Convert to fraction form
   72,173.72/99,595.69 = 39,906.47/x
3. Step 3: Cross multiply
   72,173.72x = 99,595.69 × 39,906.47
4. Step 4: Simplify right side
   72,173.72x = 3,974,511,967.02
5. Step 5: Solve for x
   x = 3,974,511,967.02/72,173.72
6. Step 6: Final answer
   x = 55,068.69