Finding the Fourth Proportional to 13,290.99, 19,940.38 and 3,931.25

Step by Step Solution

1. Step 1: Write the proportion equation
   13,290.99 : 19,940.38 = 3,931.25 : x
2. Step 2: Convert to fraction form
   13,290.99/19,940.38 = 3,931.25/x
3. Step 3: Cross multiply
   13,290.99x = 19,940.38 × 3,931.25
4. Step 4: Simplify right side
   13,290.99x = 78,390,604.13
5. Step 5: Solve for x
   x = 78,390,604.13/13,290.99
6. Step 6: Final answer
   x = 5,898.03