Finding the Fourth Proportional to 128.72, 192.96 and 64.52

Step by Step Solution

1. Step 1: Write the proportion equation
   128.72 : 192.96 = 64.52 : x
2. Step 2: Convert to fraction form
   128.72/192.96 = 64.52/x
3. Step 3: Cross multiply
   128.72x = 192.96 × 64.52
4. Step 4: Simplify right side
   128.72x = 12,449.78
5. Step 5: Solve for x
   x = 12,449.78/128.72
6. Step 6: Final answer
   x = 96.72