Finding the Fourth Proportional to 105,139.50, 145,105.88 and 69,403.92

Step by Step Solution

1. Step 1: Write the proportion equation
   105,139.50 : 145,105.88 = 69,403.92 : x
2. Step 2: Convert to fraction form
   105,139.50/145,105.88 = 69,403.92/x
3. Step 3: Cross multiply
   105,139.50x = 145,105.88 × 69,403.92
4. Step 4: Simplify right side
   105,139.50x = 10,070,916,540.03
5. Step 5: Solve for x
   x = 10,070,916,540.03/105,139.50
6. Step 6: Final answer
   x = 95,786.23