Finding the Fourth Proportional to 1,004.78, 1,386.57 and 562.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,004.78 : 1,386.57 = 562.72 : x
2. Step 2: Convert to fraction form
   1,004.78/1,386.57 = 562.72/x
3. Step 3: Cross multiply
   1,004.78x = 1,386.57 × 562.72
4. Step 4: Simplify right side
   1,004.78x = 780,250.67
5. Step 5: Solve for x
   x = 780,250.67/1,004.78
6. Step 6: Final answer
   x = 776.54