Finding the Third Proportional to 178,942 and 390,040

Step by Step Solution

1. Step 1: Write the proportion equation
   178,942 : 390,040 = 390,040 : x
2. Step 2: Convert to fraction form
   178,942/390,040 = 390,040/x
3. Step 3: Cross multiply
   178,942x = 390,040 × 390,040
4. Step 4: Simplify right side
   178,942x = 152,131,201,600
5. Step 5: Solve for x
   x = 152,131,201,600/178,942
6. Step 6: Final answer
   x = 850,170.46