Finding the Third Proportional to 1,288.88 and 2,815.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,288.88 : 2,815.69 = 2,815.69 : x
2. Step 2: Convert to fraction form
   1,288.88/2,815.69 = 2,815.69/x
3. Step 3: Cross multiply
   1,288.88x = 2,815.69 × 2,815.69
4. Step 4: Simplify right side
   1,288.88x = 7,928,096.10
5. Step 5: Solve for x
   x = 7,928,096.10/1,288.88
6. Step 6: Final answer
   x = 6,151.18