Finding the Third Proportional to 139,284 and 212,191

Step by Step Solution

1. Step 1: Write the proportion equation
   139,284 : 212,191 = 212,191 : x
2. Step 2: Convert to fraction form
   139,284/212,191 = 212,191/x
3. Step 3: Cross multiply
   139,284x = 212,191 × 212,191
4. Step 4: Simplify right side
   139,284x = 45,025,020,481
5. Step 5: Solve for x
   x = 45,025,020,481/139,284
6. Step 6: Final answer
   x = 323,260.54