Finding the Third Proportional to 4,090.78 and 6,488.16

Step by Step Solution

1. Step 1: Write the proportion equation
   4,090.78 : 6,488.16 = 6,488.16 : x
2. Step 2: Convert to fraction form
   4,090.78/6,488.16 = 6,488.16/x
3. Step 3: Cross multiply
   4,090.78x = 6,488.16 × 6,488.16
4. Step 4: Simplify right side
   4,090.78x = 42,096,171.52
5. Step 5: Solve for x
   x = 42,096,171.52/4,090.78
6. Step 6: Final answer
   x = 10,290.50