Finding the Fourth Proportional to 5,173.45, 7,139.37 and 2,815.61

Step by Step Solution

1. Step 1: Write the proportion equation
   5,173.45 : 7,139.37 = 2,815.61 : x
2. Step 2: Convert to fraction form
   5,173.45/7,139.37 = 2,815.61/x
3. Step 3: Cross multiply
   5,173.45x = 7,139.37 × 2,815.61
4. Step 4: Simplify right side
   5,173.45x = 20,101,672.83
5. Step 5: Solve for x
   x = 20,101,672.83/5,173.45
6. Step 6: Final answer
   x = 3,885.54