Finding the Fourth Proportional to 105,190.86, 145,243.89 and 69,431.70

Step by Step Solution

1. Step 1: Write the proportion equation
   105,190.86 : 145,243.89 = 69,431.70 : x
2. Step 2: Convert to fraction form
   105,190.86/145,243.89 = 69,431.70/x
3. Step 3: Cross multiply
   105,190.86x = 145,243.89 × 69,431.70
4. Step 4: Simplify right side
   105,190.86x = 10,084,530,197.31
5. Step 5: Solve for x
   x = 10,084,530,197.31/105,190.86
6. Step 6: Final answer
   x = 95,868.88