Finding the Third Proportional to 379.31 and 561.56

Step by Step Solution

1. Step 1: Write the proportion equation
   379.31 : 561.56 = 561.56 : x
2. Step 2: Convert to fraction form
   379.31/561.56 = 561.56/x
3. Step 3: Cross multiply
   379.31x = 561.56 × 561.56
4. Step 4: Simplify right side
   379.31x = 315,352.44
5. Step 5: Solve for x
   x = 315,352.44/379.31
6. Step 6: Final answer
   x = 831.38