Finding the Fourth Proportional to 128.50, 192.71 and 67.57

Step by Step Solution

1. Step 1: Write the proportion equation
   128.50 : 192.71 = 67.57 : x
2. Step 2: Convert to fraction form
   128.50/192.71 = 67.57/x
3. Step 3: Cross multiply
   128.50x = 192.71 × 67.57
4. Step 4: Simplify right side
   128.50x = 13,021.10
5. Step 5: Solve for x
   x = 13,021.10/128.50
6. Step 6: Final answer
   x = 101.33