Finding the Fourth Proportional to 1,009.31, 1,392.84 and 567.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,009.31 : 1,392.84 = 567.21 : x
2. Step 2: Convert to fraction form
   1,009.31/1,392.84 = 567.21/x
3. Step 3: Cross multiply
   1,009.31x = 1,392.84 × 567.21
4. Step 4: Simplify right side
   1,009.31x = 790,032.78
5. Step 5: Solve for x
   x = 790,032.78/1,009.31
6. Step 6: Final answer
   x = 782.75