Finding the Fourth Proportional to 8,705.31, 12,013.47 and 5,122.89

Step by Step Solution

1. Step 1: Write the proportion equation
   8,705.31 : 12,013.47 = 5,122.89 : x
2. Step 2: Convert to fraction form
   8,705.31/12,013.47 = 5,122.89/x
3. Step 3: Cross multiply
   8,705.31x = 12,013.47 × 5,122.89
4. Step 4: Simplify right side
   8,705.31x = 61,543,685.33
5. Step 5: Solve for x
   x = 61,543,685.33/8,705.31
6. Step 6: Final answer
   x = 7,069.67