Finding the Fourth Proportional to 105,478.87, 145,559.72 and 57,079.73

Step by Step Solution

1. Step 1: Write the proportion equation
   105,478.87 : 145,559.72 = 57,079.73 : x
2. Step 2: Convert to fraction form
   105,478.87/145,559.72 = 57,079.73/x
3. Step 3: Cross multiply
   105,478.87x = 145,559.72 × 57,079.73
4. Step 4: Simplify right side
   105,478.87x = 8,308,509,516.48
5. Step 5: Solve for x
   x = 8,308,509,516.48/105,478.87
6. Step 6: Final answer
   x = 78,769.42