Finding the Third Proportional to 611.56 and 830.31

Step by Step Solution

1. Step 1: Write the proportion equation
   611.56 : 830.31 = 830.31 : x
2. Step 2: Convert to fraction form
   611.56/830.31 = 830.31/x
3. Step 3: Cross multiply
   611.56x = 830.31 × 830.31
4. Step 4: Simplify right side
   611.56x = 689,418.85
5. Step 5: Solve for x
   x = 689,418.85/611.56
6. Step 6: Final answer
   x = 1,127.31