Finding the Third Proportional to 385.31 and 722.06

Step by Step Solution

1. Step 1: Write the proportion equation
   385.31 : 722.06 = 722.06 : x
2. Step 2: Convert to fraction form
   385.31/722.06 = 722.06/x
3. Step 3: Cross multiply
   385.31x = 722.06 × 722.06
4. Step 4: Simplify right side
   385.31x = 521,374.25
5. Step 5: Solve for x
   x = 521,374.25/385.31
6. Step 6: Final answer
   x = 1,353.12