Finding the Fourth Proportional to 13,499.82, 18,626.94 and 9,920.40

Step by Step Solution

1. Step 1: Write the proportion equation
   13,499.82 : 18,626.94 = 9,920.40 : x
2. Step 2: Convert to fraction form
   13,499.82/18,626.94 = 9,920.40/x
3. Step 3: Cross multiply
   13,499.82x = 18,626.94 × 9,920.40
4. Step 4: Simplify right side
   13,499.82x = 184,786,695.58
5. Step 5: Solve for x
   x = 184,786,695.58/13,499.82
6. Step 6: Final answer
   x = 13,688.09