Finding the Third Proportional to 409,509 and 619,987.50

Step by Step Solution

1. Step 1: Write the proportion equation
   409,509 : 619,987.50 = 619,987.50 : x
2. Step 2: Convert to fraction form
   409,509/619,987.50 = 619,987.50/x
3. Step 3: Cross multiply
   409,509x = 619,987.50 × 619,987.50
4. Step 4: Simplify right side
   409,509x = 384,384,500,156.25
5. Step 5: Solve for x
   x = 384,384,500,156.25/409,509
6. Step 6: Final answer
   x = 938,647.26