Finding the Third Proportional to 139,320 and 212,240

Step by Step Solution

1. Step 1: Write the proportion equation
   139,320 : 212,240 = 212,240 : x
2. Step 2: Convert to fraction form
   139,320/212,240 = 212,240/x
3. Step 3: Cross multiply
   139,320x = 212,240 × 212,240
4. Step 4: Simplify right side
   139,320x = 45,045,817,600
5. Step 5: Solve for x
   x = 45,045,817,600/139,320
6. Step 6: Final answer
   x = 323,326.28