Finding the Third Proportional to 117.25 and 216.69

Step by Step Solution

1. Step 1: Write the proportion equation
   117.25 : 216.69 = 216.69 : x
2. Step 2: Convert to fraction form
   117.25/216.69 = 216.69/x
3. Step 3: Cross multiply
   117.25x = 216.69 × 216.69
4. Step 4: Simplify right side
   117.25x = 46,953.47
5. Step 5: Solve for x
   x = 46,953.47/117.25
6. Step 6: Final answer
   x = 400.46