Finding the Fourth Proportional to 42.31, 58.39 and 22.91

Step by Step Solution

1. Step 1: Write the proportion equation
   42.31 : 58.39 = 22.91 : x
2. Step 2: Convert to fraction form
   42.31/58.39 = 22.91/x
3. Step 3: Cross multiply
   42.31x = 58.39 × 22.91
4. Step 4: Simplify right side
   42.31x = 1,337.52
5. Step 5: Solve for x
   x = 1,337.52/42.31
6. Step 6: Final answer
   x = 31.61