Finding the Third Proportional to 212,718 and 329,335.50

Step by Step Solution

1. Step 1: Write the proportion equation
   212,718 : 329,335.50 = 329,335.50 : x
2. Step 2: Convert to fraction form
   212,718/329,335.50 = 329,335.50/x
3. Step 3: Cross multiply
   212,718x = 329,335.50 × 329,335.50
4. Step 4: Simplify right side
   212,718x = 108,461,871,560.25
5. Step 5: Solve for x
   x = 108,461,871,560.25/212,718
6. Step 6: Final answer
   x = 509,885.72