Finding the Fourth Proportional to 13,119.90, 18,105.89 and 7,813.99

Step by Step Solution

1. Step 1: Write the proportion equation
   13,119.90 : 18,105.89 = 7,813.99 : x
2. Step 2: Convert to fraction form
   13,119.90/18,105.89 = 7,813.99/x
3. Step 3: Cross multiply
   13,119.90x = 18,105.89 × 7,813.99
4. Step 4: Simplify right side
   13,119.90x = 141,479,243.40
5. Step 5: Solve for x
   x = 141,479,243.40/13,119.90
6. Step 6: Final answer
   x = 10,783.56