Finding the Fourth Proportional to 123,611.10, 185,301.45 and 86,171.10

Step by Step Solution

1. Step 1: Write the proportion equation
   123,611.10 : 185,301.45 = 86,171.10 : x
2. Step 2: Convert to fraction form
   123,611.10/185,301.45 = 86,171.10/x
3. Step 3: Cross multiply
   123,611.10x = 185,301.45 × 86,171.10
4. Step 4: Simplify right side
   123,611.10x = 15,967,629,778.10
5. Step 5: Solve for x
   x = 15,967,629,778.10/123,611.10
6. Step 6: Final answer
   x = 129,176.34