Finding the Third Proportional to 140,978 and 317,445

Step by Step Solution

1. Step 1: Write the proportion equation
   140,978 : 317,445 = 317,445 : x
2. Step 2: Convert to fraction form
   140,978/317,445 = 317,445/x
3. Step 3: Cross multiply
   140,978x = 317,445 × 317,445
4. Step 4: Simplify right side
   140,978x = 100,771,328,025
5. Step 5: Solve for x
   x = 100,771,328,025/140,978
6. Step 6: Final answer
   x = 714,801.80