Finding the Fourth Proportional to 680.56, 1,016.72 and 676.96

Step by Step Solution

1. Step 1: Write the proportion equation
   680.56 : 1,016.72 = 676.96 : x
2. Step 2: Convert to fraction form
   680.56/1,016.72 = 676.96/x
3. Step 3: Cross multiply
   680.56x = 1,016.72 × 676.96
4. Step 4: Simplify right side
   680.56x = 688,278.77
5. Step 5: Solve for x
   x = 688,278.77/680.56
6. Step 6: Final answer
   x = 1,011.34