Finding the Third Proportional to 99,407.25 and 212,209.88

Step by Step Solution

1. Step 1: Write the proportion equation
   99,407.25 : 212,209.88 = 212,209.88 : x
2. Step 2: Convert to fraction form
   99,407.25/212,209.88 = 212,209.88/x
3. Step 3: Cross multiply
   99,407.25x = 212,209.88 × 212,209.88
4. Step 4: Simplify right side
   99,407.25x = 45,033,031,047.52
5. Step 5: Solve for x
   x = 45,033,031,047.52/99,407.25
6. Step 6: Final answer
   x = 453,015.56