Finding the Third Proportional to 309.94 and 498.56

Step by Step Solution

1. Step 1: Write the proportion equation
   309.94 : 498.56 = 498.56 : x
2. Step 2: Convert to fraction form
   309.94/498.56 = 498.56/x
3. Step 3: Cross multiply
   309.94x = 498.56 × 498.56
4. Step 4: Simplify right side
   309.94x = 248,564.57
5. Step 5: Solve for x
   x = 248,564.57/309.94
6. Step 6: Final answer
   x = 801.98