Finding the Fourth Proportional to 1,004.86, 1,386.72 and 556.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,004.86 : 1,386.72 = 556.73 : x
2. Step 2: Convert to fraction form
   1,004.86/1,386.72 = 556.73/x
3. Step 3: Cross multiply
   1,004.86x = 1,386.72 × 556.73
4. Step 4: Simplify right side
   1,004.86x = 772,028.63
5. Step 5: Solve for x
   x = 772,028.63/1,004.86
6. Step 6: Final answer
   x = 768.29