Finding the Fourth Proportional to 12,920.86, 19,378.72 and 3,558.45

Step by Step Solution

1. Step 1: Write the proportion equation
   12,920.86 : 19,378.72 = 3,558.45 : x
2. Step 2: Convert to fraction form
   12,920.86/19,378.72 = 3,558.45/x
3. Step 3: Cross multiply
   12,920.86x = 19,378.72 × 3,558.45
4. Step 4: Simplify right side
   12,920.86x = 68,958,188.39
5. Step 5: Solve for x
   x = 68,958,188.39/12,920.86
6. Step 6: Final answer
   x = 5,336.97