Finding the Third Proportional to 139,678 and 216,235.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,678 : 216,235.50 = 216,235.50 : x
2. Step 2: Convert to fraction form
   139,678/216,235.50 = 216,235.50/x
3. Step 3: Cross multiply
   139,678x = 216,235.50 × 216,235.50
4. Step 4: Simplify right side
   139,678x = 46,757,791,460.25
5. Step 5: Solve for x
   x = 46,757,791,460.25/139,678
6. Step 6: Final answer
   x = 334,754.16