Finding the Fourth Proportional to 1,008.78, 1,392.05 and 566.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,008.78 : 1,392.05 = 566.69 : x
2. Step 2: Convert to fraction form
   1,008.78/1,392.05 = 566.69/x
3. Step 3: Cross multiply
   1,008.78x = 1,392.05 × 566.69
4. Step 4: Simplify right side
   1,008.78x = 788,853.85
5. Step 5: Solve for x
   x = 788,853.85/1,008.78
6. Step 6: Final answer
   x = 781.99