Finding the Fourth Proportional to 42.96, 59.31 and 28.43

Step by Step Solution

1. Step 1: Write the proportion equation
   42.96 : 59.31 = 28.43 : x
2. Step 2: Convert to fraction form
   42.96/59.31 = 28.43/x
3. Step 3: Cross multiply
   42.96x = 59.31 × 28.43
4. Step 4: Simplify right side
   42.96x = 1,685.89
5. Step 5: Solve for x
   x = 1,685.89/42.96
6. Step 6: Final answer
   x = 39.24