Finding the Third Proportional to 1,389.75 and 3,031.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.75 : 3,031.50 = 3,031.50 : x
2. Step 2: Convert to fraction form
   1,389.75/3,031.50 = 3,031.50/x
3. Step 3: Cross multiply
   1,389.75x = 3,031.50 × 3,031.50
4. Step 4: Simplify right side
   1,389.75x = 9,189,992.25
5. Step 5: Solve for x
   x = 9,189,992.25/1,389.75
6. Step 6: Final answer
   x = 6,612.69