Finding the Fourth Proportional to 12,820.85, 19,228.83 and 5,430.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,820.85 : 19,228.83 = 5,430.50 : x
2. Step 2: Convert to fraction form
   12,820.85/19,228.83 = 5,430.50/x
3. Step 3: Cross multiply
   12,820.85x = 19,228.83 × 5,430.50
4. Step 4: Simplify right side
   12,820.85x = 104,422,161.32
5. Step 5: Solve for x
   x = 104,422,161.32/12,820.85
6. Step 6: Final answer
   x = 8,144.71