Finding the Third Proportional to 99,913.50 and 213,997.50

Step by Step Solution

1. Step 1: Write the proportion equation
   99,913.50 : 213,997.50 = 213,997.50 : x
2. Step 2: Convert to fraction form
   99,913.50/213,997.50 = 213,997.50/x
3. Step 3: Cross multiply
   99,913.50x = 213,997.50 × 213,997.50
4. Step 4: Simplify right side
   99,913.50x = 45,794,930,006.25
5. Step 5: Solve for x
   x = 45,794,930,006.25/99,913.50
6. Step 6: Final answer
   x = 458,345.77