Finding the Fourth Proportional to 85,934,878.88, 128,901,055.33 and 21,238,689.50

Step by Step Solution

1. Step 1: Write the proportion equation
   85,934,878.88 : 128,901,055.33 = 21,238,689.50 : x
2. Step 2: Convert to fraction form
   85,934,878.88/128,901,055.33 = 21,238,689.50/x
3. Step 3: Cross multiply
   85,934,878.88x = 128,901,055.33 × 21,238,689.50
4. Step 4: Simplify right side
   85,934,878.88x = 2,737,689,489,625,491.50
5. Step 5: Solve for x
   x = 2,737,689,489,625,491.50/85,934,878.88
6. Step 6: Final answer
   x = 31,857,722.09