Finding the Third Proportional to 413,721 and 612,805.50

Step by Step Solution

1. Step 1: Write the proportion equation
   413,721 : 612,805.50 = 612,805.50 : x
2. Step 2: Convert to fraction form
   413,721/612,805.50 = 612,805.50/x
3. Step 3: Cross multiply
   413,721x = 612,805.50 × 612,805.50
4. Step 4: Simplify right side
   413,721x = 375,530,580,830.25
5. Step 5: Solve for x
   x = 375,530,580,830.25/413,721
6. Step 6: Final answer
   x = 907,690.40