Finding the Third Proportional to 391,257 and 857,236.50

Step by Step Solution

1. Step 1: Write the proportion equation
   391,257 : 857,236.50 = 857,236.50 : x
2. Step 2: Convert to fraction form
   391,257/857,236.50 = 857,236.50/x
3. Step 3: Cross multiply
   391,257x = 857,236.50 × 857,236.50
4. Step 4: Simplify right side
   391,257x = 734,854,416,932.25
5. Step 5: Solve for x
   x = 734,854,416,932.25/391,257
6. Step 6: Final answer
   x = 1,878,188.55