Finding the Third Proportional to 298.78 and 456.73

Step by Step Solution

1. Step 1: Write the proportion equation
   298.78 : 456.73 = 456.73 : x
2. Step 2: Convert to fraction form
   298.78/456.73 = 456.73/x
3. Step 3: Cross multiply
   298.78x = 456.73 × 456.73
4. Step 4: Simplify right side
   298.78x = 208,606.29
5. Step 5: Solve for x
   x = 208,606.29/298.78
6. Step 6: Final answer
   x = 698.19