Finding the Fourth Proportional to 123,388.12, 170,287.09 and 74,978.87

Step by Step Solution

1. Step 1: Write the proportion equation
   123,388.12 : 170,287.09 = 74,978.87 : x
2. Step 2: Convert to fraction form
   123,388.12/170,287.09 = 74,978.87/x
3. Step 3: Cross multiply
   123,388.12x = 170,287.09 × 74,978.87
4. Step 4: Simplify right side
   123,388.12x = 12,767,933,583.79
5. Step 5: Solve for x
   x = 12,767,933,583.79/123,388.12
6. Step 6: Final answer
   x = 103,477.82