Finding the Fourth Proportional to 258,899.40, 388,402.06 and 109,139.72

Step by Step Solution

1. Step 1: Write the proportion equation
   258,899.40 : 388,402.06 = 109,139.72 : x
2. Step 2: Convert to fraction form
   258,899.40/388,402.06 = 109,139.72/x
3. Step 3: Cross multiply
   258,899.40x = 388,402.06 × 109,139.72
4. Step 4: Simplify right side
   258,899.40x = 42,390,092,075.82
5. Step 5: Solve for x
   x = 42,390,092,075.82/258,899.40
6. Step 6: Final answer
   x = 163,731.91