Finding the Fourth Proportional to 52,490.72, 78,748.50 and 20,902.61

Step by Step Solution

1. Step 1: Write the proportion equation
   52,490.72 : 78,748.50 = 20,902.61 : x
2. Step 2: Convert to fraction form
   52,490.72/78,748.50 = 20,902.61/x
3. Step 3: Cross multiply
   52,490.72x = 78,748.50 × 20,902.61
4. Step 4: Simplify right side
   52,490.72x = 1,646,049,183.59
5. Step 5: Solve for x
   x = 1,646,049,183.59/52,490.72
6. Step 6: Final answer
   x = 31,358.86