Finding the Fourth Proportional to 21,389,385.72, 29,516,974.32 and 12,221,831.64

Step by Step Solution

1. Step 1: Write the proportion equation
   21,389,385.72 : 29,516,974.32 = 12,221,831.64 : x
2. Step 2: Convert to fraction form
   21,389,385.72/29,516,974.32 = 12,221,831.64/x
3. Step 3: Cross multiply
   21,389,385.72x = 29,516,974.32 × 12,221,831.64
4. Step 4: Simplify right side
   21,389,385.72x = 360,751,490,661,243.50
5. Step 5: Solve for x
   x = 360,751,490,661,243.50/21,389,385.72
6. Step 6: Final answer
   x = 16,865,911.69