Finding the Third Proportional to 238.78 and 322.17

Step by Step Solution

1. Step 1: Write the proportion equation
   238.78 : 322.17 = 322.17 : x
2. Step 2: Convert to fraction form
   238.78/322.17 = 322.17/x
3. Step 3: Cross multiply
   238.78x = 322.17 × 322.17
4. Step 4: Simplify right side
   238.78x = 103,794.72
5. Step 5: Solve for x
   x = 103,794.72/238.78
6. Step 6: Final answer
   x = 434.69