Finding the Fourth Proportional to 13,209.40, 19,814.72 and 5,412.76

Step by Step Solution

1. Step 1: Write the proportion equation
   13,209.40 : 19,814.72 = 5,412.76 : x
2. Step 2: Convert to fraction form
   13,209.40/19,814.72 = 5,412.76/x
3. Step 3: Cross multiply
   13,209.40x = 19,814.72 × 5,412.76
4. Step 4: Simplify right side
   13,209.40x = 107,252,323.83
5. Step 5: Solve for x
   x = 107,252,323.83/13,209.40
6. Step 6: Final answer
   x = 8,119.39