Finding the Third Proportional to 217,716 and 336,415.50

Step by Step Solution

1. Step 1: Write the proportion equation
   217,716 : 336,415.50 = 336,415.50 : x
2. Step 2: Convert to fraction form
   217,716/336,415.50 = 336,415.50/x
3. Step 3: Cross multiply
   217,716x = 336,415.50 × 336,415.50
4. Step 4: Simplify right side
   217,716x = 113,175,388,640.25
5. Step 5: Solve for x
   x = 113,175,388,640.25/217,716
6. Step 6: Final answer
   x = 519,830.37