Finding the Fourth Proportional to 72,780.47, 109,170.10 and 20,189.96

Step by Step Solution

1. Step 1: Write the proportion equation
   72,780.47 : 109,170.10 = 20,189.96 : x
2. Step 2: Convert to fraction form
   72,780.47/109,170.10 = 20,189.96/x
3. Step 3: Cross multiply
   72,780.47x = 109,170.10 × 20,189.96
4. Step 4: Simplify right side
   72,780.47x = 2,204,139,897.76
5. Step 5: Solve for x
   x = 2,204,139,897.76/72,780.47
6. Step 6: Final answer
   x = 30,284.77