Finding the Third Proportional to 139,819.50 and 218,011.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,819.50 : 218,011.50 = 218,011.50 : x
2. Step 2: Convert to fraction form
   139,819.50/218,011.50 = 218,011.50/x
3. Step 3: Cross multiply
   139,819.50x = 218,011.50 × 218,011.50
4. Step 4: Simplify right side
   139,819.50x = 47,529,014,132.25
5. Step 5: Solve for x
   x = 47,529,014,132.25/139,819.50
6. Step 6: Final answer
   x = 339,931.23