Finding the Third Proportional to 338,437.50 and 721,911

Step by Step Solution

1. Step 1: Write the proportion equation
   338,437.50 : 721,911 = 721,911 : x
2. Step 2: Convert to fraction form
   338,437.50/721,911 = 721,911/x
3. Step 3: Cross multiply
   338,437.50x = 721,911 × 721,911
4. Step 4: Simplify right side
   338,437.50x = 521,155,491,921
5. Step 5: Solve for x
   x = 521,155,491,921/338,437.50
6. Step 6: Final answer
   x = 1,539,886.96