Finding the Third Proportional to 379.37 and 512.31

Step by Step Solution

1. Step 1: Write the proportion equation
   379.37 : 512.31 = 512.31 : x
2. Step 2: Convert to fraction form
   379.37/512.31 = 512.31/x
3. Step 3: Cross multiply
   379.37x = 512.31 × 512.31
4. Step 4: Simplify right side
   379.37x = 262,466.10
5. Step 5: Solve for x
   x = 262,466.10/379.37
6. Step 6: Final answer
   x = 691.85