Finding the Fourth Proportional to 128.27, 192.42 and 59.78

Step by Step Solution

1. Step 1: Write the proportion equation
   128.27 : 192.42 = 59.78 : x
2. Step 2: Convert to fraction form
   128.27/192.42 = 59.78/x
3. Step 3: Cross multiply
   128.27x = 192.42 × 59.78
4. Step 4: Simplify right side
   128.27x = 11,501.91
5. Step 5: Solve for x
   x = 11,501.91/128.27
6. Step 6: Final answer
   x = 89.67