Finding the Fourth Proportional to 12,399.50, 17,111.58 and 6,810.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,399.50 : 17,111.58 = 6,810.50 : x
2. Step 2: Convert to fraction form
   12,399.50/17,111.58 = 6,810.50/x
3. Step 3: Cross multiply
   12,399.50x = 17,111.58 × 6,810.50
4. Step 4: Simplify right side
   12,399.50x = 116,538,415.59
5. Step 5: Solve for x
   x = 116,538,415.59/12,399.50
6. Step 6: Final answer
   x = 9,398.64