Finding the Fourth Proportional to 123,610.71, 170,610.62 and 72,639.81

Step by Step Solution

1. Step 1: Write the proportion equation
   123,610.71 : 170,610.62 = 72,639.81 : x
2. Step 2: Convert to fraction form
   123,610.71/170,610.62 = 72,639.81/x
3. Step 3: Cross multiply
   123,610.71x = 170,610.62 × 72,639.81
4. Step 4: Simplify right side
   123,610.71x = 12,393,123,020.78
5. Step 5: Solve for x
   x = 12,393,123,020.78/123,610.71
6. Step 6: Final answer
   x = 100,259.30