Finding the Fourth Proportional to 1,009.39, 1,392.89 and 567.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,009.39 : 1,392.89 = 567.21 : x
2. Step 2: Convert to fraction form
   1,009.39/1,392.89 = 567.21/x
3. Step 3: Cross multiply
   1,009.39x = 1,392.89 × 567.21
4. Step 4: Simplify right side
   1,009.39x = 790,061.14
5. Step 5: Solve for x
   x = 790,061.14/1,009.39
6. Step 6: Final answer
   x = 782.71