Finding the Third Proportional to 289,245 and 443,707.50

Step by Step Solution

1. Step 1: Write the proportion equation
   289,245 : 443,707.50 = 443,707.50 : x
2. Step 2: Convert to fraction form
   289,245/443,707.50 = 443,707.50/x
3. Step 3: Cross multiply
   289,245x = 443,707.50 × 443,707.50
4. Step 4: Simplify right side
   289,245x = 196,876,345,556.25
5. Step 5: Solve for x
   x = 196,876,345,556.25/289,245
6. Step 6: Final answer
   x = 680,656.00