Finding the Fourth Proportional to 1,005.89, 1,388.23 and 563.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.89 : 1,388.23 = 563.87 : x
2. Step 2: Convert to fraction form
   1,005.89/1,388.23 = 563.87/x
3. Step 3: Cross multiply
   1,005.89x = 1,388.23 × 563.87
4. Step 4: Simplify right side
   1,005.89x = 782,781.25
5. Step 5: Solve for x
   x = 782,781.25/1,005.89
6. Step 6: Final answer
   x = 778.20