Finding the Fourth Proportional to 105,359.67, 145,472.49 and 65,128.59

Step by Step Solution

1. Step 1: Write the proportion equation
   105,359.67 : 145,472.49 = 65,128.59 : x
2. Step 2: Convert to fraction form
   105,359.67/145,472.49 = 65,128.59/x
3. Step 3: Cross multiply
   105,359.67x = 145,472.49 × 65,128.59
4. Step 4: Simplify right side
   105,359.67x = 9,474,418,157.49
5. Step 5: Solve for x
   x = 9,474,418,157.49/105,359.67
6. Step 6: Final answer
   x = 89,924.52