Finding the Third Proportional to 2,645.81 and 3,889.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,645.81 : 3,889.69 = 3,889.69 : x
2. Step 2: Convert to fraction form
   2,645.81/3,889.69 = 3,889.69/x
3. Step 3: Cross multiply
   2,645.81x = 3,889.69 × 3,889.69
4. Step 4: Simplify right side
   2,645.81x = 15,129,668.85
5. Step 5: Solve for x
   x = 15,129,668.85/2,645.81
6. Step 6: Final answer
   x = 5,718.35