Finding the Third Proportional to 90,380 and 138,258

Step by Step Solution

1. Step 1: Write the proportion equation
   90,380 : 138,258 = 138,258 : x
2. Step 2: Convert to fraction form
   90,380/138,258 = 138,258/x
3. Step 3: Cross multiply
   90,380x = 138,258 × 138,258
4. Step 4: Simplify right side
   90,380x = 19,115,274,564
5. Step 5: Solve for x
   x = 19,115,274,564/90,380
6. Step 6: Final answer
   x = 211,498.94