Finding the Fourth Proportional to 81,128.49, 111,957.31 and 45,318.50

Step by Step Solution

1. Step 1: Write the proportion equation
   81,128.49 : 111,957.31 = 45,318.50 : x
2. Step 2: Convert to fraction form
   81,128.49/111,957.31 = 45,318.50/x
3. Step 3: Cross multiply
   81,128.49x = 111,957.31 × 45,318.50
4. Step 4: Simplify right side
   81,128.49x = 5,073,737,554.83
5. Step 5: Solve for x
   x = 5,073,737,554.83/81,128.49
6. Step 6: Final answer
   x = 62,539.53