Finding the Fourth Proportional to 171,788.87, 257,769.25 and 77,086.78

Step by Step Solution

1. Step 1: Write the proportion equation
   171,788.87 : 257,769.25 = 77,086.78 : x
2. Step 2: Convert to fraction form
   171,788.87/257,769.25 = 77,086.78/x
3. Step 3: Cross multiply
   171,788.87x = 257,769.25 × 77,086.78
4. Step 4: Simplify right side
   171,788.87x = 19,870,601,465.52
5. Step 5: Solve for x
   x = 19,870,601,465.52/171,788.87
6. Step 6: Final answer
   x = 115,668.74