Finding the Fourth Proportional to 13,290.55, 19,939.72 and 3,930.81

Step by Step Solution

1. Step 1: Write the proportion equation
   13,290.55 : 19,939.72 = 3,930.81 : x
2. Step 2: Convert to fraction form
   13,290.55/19,939.72 = 3,930.81/x
3. Step 3: Cross multiply
   13,290.55x = 19,939.72 × 3,930.81
4. Step 4: Simplify right side
   13,290.55x = 78,379,285.70
5. Step 5: Solve for x
   x = 78,379,285.70/13,290.55
6. Step 6: Final answer
   x = 5,897.37