Finding the Third Proportional to 2,543.91 and 5,290.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,543.91 : 5,290.31 = 5,290.31 : x
2. Step 2: Convert to fraction form
   2,543.91/5,290.31 = 5,290.31/x
3. Step 3: Cross multiply
   2,543.91x = 5,290.31 × 5,290.31
4. Step 4: Simplify right side
   2,543.91x = 27,987,406.35
5. Step 5: Solve for x
   x = 27,987,406.35/2,543.91
6. Step 6: Final answer
   x = 11,001.74