Finding the Fourth Proportional to 105,519.98, 145,616.29 and 57,772.31

Step by Step Solution

1. Step 1: Write the proportion equation
   105,519.98 : 145,616.29 = 57,772.31 : x
2. Step 2: Convert to fraction form
   105,519.98/145,616.29 = 57,772.31/x
3. Step 3: Cross multiply
   105,519.98x = 145,616.29 × 57,772.31
4. Step 4: Simplify right side
   105,519.98x = 8,412,588,574.42
5. Step 5: Solve for x
   x = 8,412,588,574.42/105,519.98
6. Step 6: Final answer
   x = 79,725.08