Finding the Third Proportional to 90,312 and 139,564

Step by Step Solution

1. Step 1: Write the proportion equation
   90,312 : 139,564 = 139,564 : x
2. Step 2: Convert to fraction form
   90,312/139,564 = 139,564/x
3. Step 3: Cross multiply
   90,312x = 139,564 × 139,564
4. Step 4: Simplify right side
   90,312x = 19,478,110,096
5. Step 5: Solve for x
   x = 19,478,110,096/90,312
6. Step 6: Final answer
   x = 215,675.77