Finding the Fourth Proportional to 21,105.31, 31,669.50 and 7,069.63

Step by Step Solution

1. Step 1: Write the proportion equation
   21,105.31 : 31,669.50 = 7,069.63 : x
2. Step 2: Convert to fraction form
   21,105.31/31,669.50 = 7,069.63/x
3. Step 3: Cross multiply
   21,105.31x = 31,669.50 × 7,069.63
4. Step 4: Simplify right side
   21,105.31x = 223,891,647.29
5. Step 5: Solve for x
   x = 223,891,647.29/21,105.31
6. Step 6: Final answer
   x = 10,608.31