Finding the Fourth Proportional to 128.69, 192.96 and 74.69

Step by Step Solution

1. Step 1: Write the proportion equation
   128.69 : 192.96 = 74.69 : x
2. Step 2: Convert to fraction form
   128.69/192.96 = 74.69/x
3. Step 3: Cross multiply
   128.69x = 192.96 × 74.69
4. Step 4: Simplify right side
   128.69x = 14,411.22
5. Step 5: Solve for x
   x = 14,411.22/128.69
6. Step 6: Final answer
   x = 111.99