Finding the Third Proportional to 639,178 and 1,391,108

Step by Step Solution

1. Step 1: Write the proportion equation
   639,178 : 1,391,108 = 1,391,108 : x
2. Step 2: Convert to fraction form
   639,178/1,391,108 = 1,391,108/x
3. Step 3: Cross multiply
   639,178x = 1,391,108 × 1,391,108
4. Step 4: Simplify right side
   639,178x = 1,935,181,467,664
5. Step 5: Solve for x
   x = 1,935,181,467,664/639,178
6. Step 6: Final answer
   x = 3,027,609.63