Finding the Third Proportional to 354,720 and 521,707.50

Step by Step Solution

1. Step 1: Write the proportion equation
   354,720 : 521,707.50 = 521,707.50 : x
2. Step 2: Convert to fraction form
   354,720/521,707.50 = 521,707.50/x
3. Step 3: Cross multiply
   354,720x = 521,707.50 × 521,707.50
4. Step 4: Simplify right side
   354,720x = 272,178,715,556.25
5. Step 5: Solve for x
   x = 272,178,715,556.25/354,720
6. Step 6: Final answer
   x = 767,305.81