Finding the Fourth Proportional to 128.82, 193.25 and 71.07

Step by Step Solution

1. Step 1: Write the proportion equation
   128.82 : 193.25 = 71.07 : x
2. Step 2: Convert to fraction form
   128.82/193.25 = 71.07/x
3. Step 3: Cross multiply
   128.82x = 193.25 × 71.07
4. Step 4: Simplify right side
   128.82x = 13,734.82
5. Step 5: Solve for x
   x = 13,734.82/128.82
6. Step 6: Final answer
   x = 106.62