Finding the Third Proportional to 559.31 and 1,320.56

Step by Step Solution

1. Step 1: Write the proportion equation
   559.31 : 1,320.56 = 1,320.56 : x
2. Step 2: Convert to fraction form
   559.31/1,320.56 = 1,320.56/x
3. Step 3: Cross multiply
   559.31x = 1,320.56 × 1,320.56
4. Step 4: Simplify right side
   559.31x = 1,743,885.32
5. Step 5: Solve for x
   x = 1,743,885.32/559.31
6. Step 6: Final answer
   x = 3,117.91