Finding the Fourth Proportional to 3,499.61, 5,251.62 and 3,171.21

Step by Step Solution

1. Step 1: Write the proportion equation
   3,499.61 : 5,251.62 = 3,171.21 : x
2. Step 2: Convert to fraction form
   3,499.61/5,251.62 = 3,171.21/x
3. Step 3: Cross multiply
   3,499.61x = 5,251.62 × 3,171.21
4. Step 4: Simplify right side
   3,499.61x = 16,653,989.86
5. Step 5: Solve for x
   x = 16,653,989.86/3,499.61
6. Step 6: Final answer
   x = 4,758.82