Finding the Third Proportional to 478,929 and 639,070.50

Step by Step Solution

1. Step 1: Write the proportion equation
   478,929 : 639,070.50 = 639,070.50 : x
2. Step 2: Convert to fraction form
   478,929/639,070.50 = 639,070.50/x
3. Step 3: Cross multiply
   478,929x = 639,070.50 × 639,070.50
4. Step 4: Simplify right side
   478,929x = 408,411,103,970.25
5. Step 5: Solve for x
   x = 408,411,103,970.25/478,929
6. Step 6: Final answer
   x = 852,759.19