Finding the Third Proportional to 139,261 and 212,155.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,261 : 212,155.50 = 212,155.50 : x
2. Step 2: Convert to fraction form
   139,261/212,155.50 = 212,155.50/x
3. Step 3: Cross multiply
   139,261x = 212,155.50 × 212,155.50
4. Step 4: Simplify right side
   139,261x = 45,009,956,180.25
5. Step 5: Solve for x
   x = 45,009,956,180.25/139,261
6. Step 6: Final answer
   x = 323,205.75