Finding the Third Proportional to 397.31 and 607.78

Step by Step Solution

1. Step 1: Write the proportion equation
   397.31 : 607.78 = 607.78 : x
2. Step 2: Convert to fraction form
   397.31/607.78 = 607.78/x
3. Step 3: Cross multiply
   397.31x = 607.78 × 607.78
4. Step 4: Simplify right side
   397.31x = 369,398.05
5. Step 5: Solve for x
   x = 369,398.05/397.31
6. Step 6: Final answer
   x = 929.74