Finding the Fourth Proportional to 21,109,957,236.72, 29,118,354,185.52 and 12,968,197,835.76

Step by Step Solution

1. Step 1: Write the proportion equation
   21,109,957,236.72 : 29,118,354,185.52 = 12,968,197,835.76 : x
2. Step 2: Convert to fraction form
   21,109,957,236.72/29,118,354,185.52 = 12,968,197,835.76/x
3. Step 3: Cross multiply
   21,109,957,236.72x = 29,118,354,185.52 × 12,968,197,835.76
4. Step 4: Simplify right side
   21,109,957,236.72x = 377,612,577,729,553,629,184
5. Step 5: Solve for x
   x = 377,612,577,729,553,629,184/21,109,957,236.72
6. Step 6: Final answer
   x = 17,887,889,278.75