Finding the Fourth Proportional to 127.69, 191.23 and 97.31

Step by Step Solution

1. Step 1: Write the proportion equation
   127.69 : 191.23 = 97.31 : x
2. Step 2: Convert to fraction form
   127.69/191.23 = 97.31/x
3. Step 3: Cross multiply
   127.69x = 191.23 × 97.31
4. Step 4: Simplify right side
   127.69x = 18,608.83
5. Step 5: Solve for x
   x = 18,608.83/127.69
6. Step 6: Final answer
   x = 145.74