Finding the Fourth Proportional to 105,426.87, 145,492.57 and 57,680.23

Step by Step Solution

1. Step 1: Write the proportion equation
   105,426.87 : 145,492.57 = 57,680.23 : x
2. Step 2: Convert to fraction form
   105,426.87/145,492.57 = 57,680.23/x
3. Step 3: Cross multiply
   105,426.87x = 145,492.57 × 57,680.23
4. Step 4: Simplify right side
   105,426.87x = 8,392,044,900.89
5. Step 5: Solve for x
   x = 8,392,044,900.89/105,426.87
6. Step 6: Final answer
   x = 79,600.63