Finding the Fourth Proportional to 11,947.31, 16,487.25 and 6,642.12

Step by Step Solution

1. Step 1: Write the proportion equation
   11,947.31 : 16,487.25 = 6,642.12 : x
2. Step 2: Convert to fraction form
   11,947.31/16,487.25 = 6,642.12/x
3. Step 3: Cross multiply
   11,947.31x = 16,487.25 × 6,642.12
4. Step 4: Simplify right side
   11,947.31x = 109,510,329.89
5. Step 5: Solve for x
   x = 109,510,329.89/11,947.31
6. Step 6: Final answer
   x = 9,166.11