Finding the Fourth Proportional to 128.39, 191.33 and 123.93

Step by Step Solution

1. Step 1: Write the proportion equation
   128.39 : 191.33 = 123.93 : x
2. Step 2: Convert to fraction form
   128.39/191.33 = 123.93/x
3. Step 3: Cross multiply
   128.39x = 191.33 × 123.93
4. Step 4: Simplify right side
   128.39x = 23,710.91
5. Step 5: Solve for x
   x = 23,710.91/128.39
6. Step 6: Final answer
   x = 184.69