Finding the Third Proportional to 99,297.50 and 212,808.50

Step by Step Solution

1. Step 1: Write the proportion equation
   99,297.50 : 212,808.50 = 212,808.50 : x
2. Step 2: Convert to fraction form
   99,297.50/212,808.50 = 212,808.50/x
3. Step 3: Cross multiply
   99,297.50x = 212,808.50 × 212,808.50
4. Step 4: Simplify right side
   99,297.50x = 45,287,457,672.25
5. Step 5: Solve for x
   x = 45,287,457,672.25/99,297.50
6. Step 6: Final answer
   x = 456,078.53