Finding the Third Proportional to 120,031.50 and 258,666

Step by Step Solution

1. Step 1: Write the proportion equation
   120,031.50 : 258,666 = 258,666 : x
2. Step 2: Convert to fraction form
   120,031.50/258,666 = 258,666/x
3. Step 3: Cross multiply
   120,031.50x = 258,666 × 258,666
4. Step 4: Simplify right side
   120,031.50x = 66,908,099,556
5. Step 5: Solve for x
   x = 66,908,099,556/120,031.50
6. Step 6: Final answer
   x = 557,421.17