Finding the Fourth Proportional to 8,421.98, 11,619.50 and 5,439.83

Step by Step Solution

1. Step 1: Write the proportion equation
   8,421.98 : 11,619.50 = 5,439.83 : x
2. Step 2: Convert to fraction form
   8,421.98/11,619.50 = 5,439.83/x
3. Step 3: Cross multiply
   8,421.98x = 11,619.50 × 5,439.83
4. Step 4: Simplify right side
   8,421.98x = 63,208,019.39
5. Step 5: Solve for x
   x = 63,208,019.39/8,421.98
6. Step 6: Final answer
   x = 7,505.13