Finding the Third Proportional to 139,280 and 212,184

Step by Step Solution

1. Step 1: Write the proportion equation
   139,280 : 212,184 = 212,184 : x
2. Step 2: Convert to fraction form
   139,280/212,184 = 212,184/x
3. Step 3: Cross multiply
   139,280x = 212,184 × 212,184
4. Step 4: Simplify right side
   139,280x = 45,022,049,856
5. Step 5: Solve for x
   x = 45,022,049,856/139,280
6. Step 6: Final answer
   x = 323,248.49