Finding the Third Proportional to 128.74 and 196.38

Step by Step Solution

1. Step 1: Write the proportion equation
   128.74 : 196.38 = 196.38 : x
2. Step 2: Convert to fraction form
   128.74/196.38 = 196.38/x
3. Step 3: Cross multiply
   128.74x = 196.38 × 196.38
4. Step 4: Simplify right side
   128.74x = 38,566.21
5. Step 5: Solve for x
   x = 38,566.21/128.74
6. Step 6: Final answer
   x = 299.56