Finding the Third Proportional to 188.72 and 398.06

Step by Step Solution

1. Step 1: Write the proportion equation
   188.72 : 398.06 = 398.06 : x
2. Step 2: Convert to fraction form
   188.72/398.06 = 398.06/x
3. Step 3: Cross multiply
   188.72x = 398.06 × 398.06
4. Step 4: Simplify right side
   188.72x = 158,453.75
5. Step 5: Solve for x
   x = 158,453.75/188.72
6. Step 6: Final answer
   x = 839.63