Finding the Third Proportional to 138,799.50 and 298,647

Step by Step Solution

1. Step 1: Write the proportion equation
   138,799.50 : 298,647 = 298,647 : x
2. Step 2: Convert to fraction form
   138,799.50/298,647 = 298,647/x
3. Step 3: Cross multiply
   138,799.50x = 298,647 × 298,647
4. Step 4: Simplify right side
   138,799.50x = 89,190,030,609
5. Step 5: Solve for x
   x = 89,190,030,609/138,799.50
6. Step 6: Final answer
   x = 642,581.79