Finding the Fourth Proportional to 21,068.10, 31,598.51 and 7,920.59

Step by Step Solution

1. Step 1: Write the proportion equation
   21,068.10 : 31,598.51 = 7,920.59 : x
2. Step 2: Convert to fraction form
   21,068.10/31,598.51 = 7,920.59/x
3. Step 3: Cross multiply
   21,068.10x = 31,598.51 × 7,920.59
4. Step 4: Simplify right side
   21,068.10x = 250,278,644.73
5. Step 5: Solve for x
   x = 250,278,644.73/21,068.10
6. Step 6: Final answer
   x = 11,879.51