Finding the Fourth Proportional to 5,173.59, 7,139.72 and 2,815.89

Step by Step Solution

1. Step 1: Write the proportion equation
   5,173.59 : 7,139.72 = 2,815.89 : x
2. Step 2: Convert to fraction form
   5,173.59/7,139.72 = 2,815.89/x
3. Step 3: Cross multiply
   5,173.59x = 7,139.72 × 2,815.89
4. Step 4: Simplify right side
   5,173.59x = 20,104,652.07
5. Step 5: Solve for x
   x = 20,104,652.07/5,173.59
6. Step 6: Final answer
   x = 3,886.02