Finding the Fourth Proportional to 20,985,766.79, 28,960,418.15 and 12,166,931.91

Step by Step Solution

1. Step 1: Write the proportion equation
   20,985,766.79 : 28,960,418.15 = 12,166,931.91 : x
2. Step 2: Convert to fraction form
   20,985,766.79/28,960,418.15 = 12,166,931.91/x
3. Step 3: Cross multiply
   20,985,766.79x = 28,960,418.15 × 12,166,931.91
4. Step 4: Simplify right side
   20,985,766.79x = 352,359,435,510,541.38
5. Step 5: Solve for x
   x = 352,359,435,510,541.38/20,985,766.79
6. Step 6: Final answer
   x = 16,790,400.80