Finding the Third Proportional to 1,287.56 and 2,772.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,287.56 : 2,772.56 = 2,772.56 : x
2. Step 2: Convert to fraction form
   1,287.56/2,772.56 = 2,772.56/x
3. Step 3: Cross multiply
   1,287.56x = 2,772.56 × 2,772.56
4. Step 4: Simplify right side
   1,287.56x = 7,687,102.82
5. Step 5: Solve for x
   x = 7,687,102.82/1,287.56
6. Step 6: Final answer
   x = 5,970.28