Finding the Fourth Proportional to 1,008.77, 1,391.96 and 566.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,008.77 : 1,391.96 = 566.56 : x
2. Step 2: Convert to fraction form
   1,008.77/1,391.96 = 566.56/x
3. Step 3: Cross multiply
   1,008.77x = 1,391.96 × 566.56
4. Step 4: Simplify right side
   1,008.77x = 788,632.01
5. Step 5: Solve for x
   x = 788,632.01/1,008.77
6. Step 6: Final answer
   x = 781.78