Finding the Fourth Proportional to 28.38, 42.56 and 19.42

Step by Step Solution

1. Step 1: Write the proportion equation
   28.38 : 42.56 = 19.42 : x
2. Step 2: Convert to fraction form
   28.38/42.56 = 19.42/x
3. Step 3: Cross multiply
   28.38x = 42.56 × 19.42
4. Step 4: Simplify right side
   28.38x = 826.52
5. Step 5: Solve for x
   x = 826.52/28.38
6. Step 6: Final answer
   x = 29.12