Finding the Fourth Proportional to 42.84, 59.15 and 28.31

Step by Step Solution

1. Step 1: Write the proportion equation
   42.84 : 59.15 = 28.31 : x
2. Step 2: Convert to fraction form
   42.84/59.15 = 28.31/x
3. Step 3: Cross multiply
   42.84x = 59.15 × 28.31
4. Step 4: Simplify right side
   42.84x = 1,674.10
5. Step 5: Solve for x
   x = 1,674.10/42.84
6. Step 6: Final answer
   x = 39.08