Finding the Third Proportional to 397,320 and 866,040

Step by Step Solution

1. Step 1: Write the proportion equation
   397,320 : 866,040 = 866,040 : x
2. Step 2: Convert to fraction form
   397,320/866,040 = 866,040/x
3. Step 3: Cross multiply
   397,320x = 866,040 × 866,040
4. Step 4: Simplify right side
   397,320x = 750,025,281,600
5. Step 5: Solve for x
   x = 750,025,281,600/397,320
6. Step 6: Final answer
   x = 1,887,710.87