Finding the Third Proportional to 2,556.56 and 3,990.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,556.56 : 3,990.52 = 3,990.52 : x
2. Step 2: Convert to fraction form
   2,556.56/3,990.52 = 3,990.52/x
3. Step 3: Cross multiply
   2,556.56x = 3,990.52 × 3,990.52
4. Step 4: Simplify right side
   2,556.56x = 15,924,214.95
5. Step 5: Solve for x
   x = 15,924,214.95/2,556.56
6. Step 6: Final answer
   x = 6,228.76