Finding the Fourth Proportional to 123,168.78, 169,972.83 and 66,580.17

Step by Step Solution

1. Step 1: Write the proportion equation
   123,168.78 : 169,972.83 = 66,580.17 : x
2. Step 2: Convert to fraction form
   123,168.78/169,972.83 = 66,580.17/x
3. Step 3: Cross multiply
   123,168.78x = 169,972.83 × 66,580.17
4. Step 4: Simplify right side
   123,168.78x = 11,316,819,916.78
5. Step 5: Solve for x
   x = 11,316,819,916.78/123,168.78
6. Step 6: Final answer
   x = 91,880.59