Finding the Third Proportional to 31,408 and 68,216

Step by Step Solution

1. Step 1: Write the proportion equation
   31,408 : 68,216 = 68,216 : x
2. Step 2: Convert to fraction form
   31,408/68,216 = 68,216/x
3. Step 3: Cross multiply
   31,408x = 68,216 × 68,216
4. Step 4: Simplify right side
   31,408x = 4,653,422,656
5. Step 5: Solve for x
   x = 4,653,422,656/31,408
6. Step 6: Final answer
   x = 148,160.43