Finding the Third Proportional to 3,996.98 and 5,590.90

Step by Step Solution

1. Step 1: Write the proportion equation
   3,996.98 : 5,590.90 = 5,590.90 : x
2. Step 2: Convert to fraction form
   3,996.98/5,590.90 = 5,590.90/x
3. Step 3: Cross multiply
   3,996.98x = 5,590.90 × 5,590.90
4. Step 4: Simplify right side
   3,996.98x = 31,258,145.34
5. Step 5: Solve for x
   x = 31,258,145.34/3,996.98
6. Step 6: Final answer
   x = 7,820.43