Finding the Third Proportional to 1,287.94 and 2,591.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,287.94 : 2,591.06 = 2,591.06 : x
2. Step 2: Convert to fraction form
   1,287.94/2,591.06 = 2,591.06/x
3. Step 3: Cross multiply
   1,287.94x = 2,591.06 × 2,591.06
4. Step 4: Simplify right side
   1,287.94x = 6,713,604.88
5. Step 5: Solve for x
   x = 6,713,604.88/1,287.94
6. Step 6: Final answer
   x = 5,212.68