Finding the Third Proportional to 128,059.50 and 212,353.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,059.50 : 212,353.50 = 212,353.50 : x
2. Step 2: Convert to fraction form
   128,059.50/212,353.50 = 212,353.50/x
3. Step 3: Cross multiply
   128,059.50x = 212,353.50 × 212,353.50
4. Step 4: Simplify right side
   128,059.50x = 45,094,008,962.25
5. Step 5: Solve for x
   x = 45,094,008,962.25/128,059.50
6. Step 6: Final answer
   x = 352,133.26