Finding the Third Proportional to 231.61 and 381.59

Step by Step Solution

1. Step 1: Write the proportion equation
   231.61 : 381.59 = 381.59 : x
2. Step 2: Convert to fraction form
   231.61/381.59 = 381.59/x
3. Step 3: Cross multiply
   231.61x = 381.59 × 381.59
4. Step 4: Simplify right side
   231.61x = 145,607.83
5. Step 5: Solve for x
   x = 145,607.83/231.61
6. Step 6: Final answer
   x = 628.68