Finding the Fourth Proportional to 13,115.72, 18,091.32 and 7,806.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,115.72 : 18,091.32 = 7,806.50 : x
2. Step 2: Convert to fraction form
   13,115.72/18,091.32 = 7,806.50/x
3. Step 3: Cross multiply
   13,115.72x = 18,091.32 × 7,806.50
4. Step 4: Simplify right side
   13,115.72x = 141,229,889.58
5. Step 5: Solve for x
   x = 141,229,889.58/13,115.72
6. Step 6: Final answer
   x = 10,767.99