Finding the Fourth Proportional to 30,528.54, 42,105.69 and 20,453.76

Step by Step Solution

1. Step 1: Write the proportion equation
   30,528.54 : 42,105.69 = 20,453.76 : x
2. Step 2: Convert to fraction form
   30,528.54/42,105.69 = 20,453.76/x
3. Step 3: Cross multiply
   30,528.54x = 42,105.69 × 20,453.76
4. Step 4: Simplify right side
   30,528.54x = 861,219,677.89
5. Step 5: Solve for x
   x = 861,219,677.89/30,528.54
6. Step 6: Final answer
   x = 28,210.31