Finding the Fourth Proportional to 105,589.92, 145,658.88 and 65,290.80

Step by Step Solution

1. Step 1: Write the proportion equation
   105,589.92 : 145,658.88 = 65,290.80 : x
2. Step 2: Convert to fraction form
   105,589.92/145,658.88 = 65,290.80/x
3. Step 3: Cross multiply
   105,589.92x = 145,658.88 × 65,290.80
4. Step 4: Simplify right side
   105,589.92x = 9,510,184,802.30
5. Step 5: Solve for x
   x = 9,510,184,802.30/105,589.92
6. Step 6: Final answer
   x = 90,067.17