Finding the Fourth Proportional to 28,470.89, 42,669.18 and 20,599.92

Step by Step Solution

1. Step 1: Write the proportion equation
   28,470.89 : 42,669.18 = 20,599.92 : x
2. Step 2: Convert to fraction form
   28,470.89/42,669.18 = 20,599.92/x
3. Step 3: Cross multiply
   28,470.89x = 42,669.18 × 20,599.92
4. Step 4: Simplify right side
   28,470.89x = 878,981,694.47
5. Step 5: Solve for x
   x = 878,981,694.47/28,470.89
6. Step 6: Final answer
   x = 30,872.99