Finding the Fourth Proportional to 105,559.50, 145,673.69 and 57,817.30

Step by Step Solution

1. Step 1: Write the proportion equation
   105,559.50 : 145,673.69 = 57,817.30 : x
2. Step 2: Convert to fraction form
   105,559.50/145,673.69 = 57,817.30/x
3. Step 3: Cross multiply
   105,559.50x = 145,673.69 × 57,817.30
4. Step 4: Simplify right side
   105,559.50x = 8,422,459,436.84
5. Step 5: Solve for x
   x = 8,422,459,436.84/105,559.50
6. Step 6: Final answer
   x = 79,788.74