Finding the Third Proportional to 138,856 and 309,968

Step by Step Solution

1. Step 1: Write the proportion equation
   138,856 : 309,968 = 309,968 : x
2. Step 2: Convert to fraction form
   138,856/309,968 = 309,968/x
3. Step 3: Cross multiply
   138,856x = 309,968 × 309,968
4. Step 4: Simplify right side
   138,856x = 96,080,161,024
5. Step 5: Solve for x
   x = 96,080,161,024/138,856
6. Step 6: Final answer
   x = 691,941.01