Finding the Third Proportional to 299,412 and 646,800.75

Step by Step Solution

1. Step 1: Write the proportion equation
   299,412 : 646,800.75 = 646,800.75 : x
2. Step 2: Convert to fraction form
   299,412/646,800.75 = 646,800.75/x
3. Step 3: Cross multiply
   299,412x = 646,800.75 × 646,800.75
4. Step 4: Simplify right side
   299,412x = 418,351,210,200.56
5. Step 5: Solve for x
   x = 418,351,210,200.56/299,412
6. Step 6: Final answer
   x = 1,397,242.63