Finding the Third Proportional to 385,890 and 550,459.50

Step by Step Solution

1. Step 1: Write the proportion equation
   385,890 : 550,459.50 = 550,459.50 : x
2. Step 2: Convert to fraction form
   385,890/550,459.50 = 550,459.50/x
3. Step 3: Cross multiply
   385,890x = 550,459.50 × 550,459.50
4. Step 4: Simplify right side
   385,890x = 303,005,661,140.25
5. Step 5: Solve for x
   x = 303,005,661,140.25/385,890
6. Step 6: Final answer
   x = 785,212.52