Finding the Third Proportional to 223.31 and 306.56

Step by Step Solution

1. Step 1: Write the proportion equation
   223.31 : 306.56 = 306.56 : x
2. Step 2: Convert to fraction form
   223.31/306.56 = 306.56/x
3. Step 3: Cross multiply
   223.31x = 306.56 × 306.56
4. Step 4: Simplify right side
   223.31x = 93,980.57
5. Step 5: Solve for x
   x = 93,980.57/223.31
6. Step 6: Final answer
   x = 420.85