Finding the Fourth Proportional to 28.24, 42.37 and 28.15

Step by Step Solution

1. Step 1: Write the proportion equation
   28.24 : 42.37 = 28.15 : x
2. Step 2: Convert to fraction form
   28.24/42.37 = 28.15/x
3. Step 3: Cross multiply
   28.24x = 42.37 × 28.15
4. Step 4: Simplify right side
   28.24x = 1,192.54
5. Step 5: Solve for x
   x = 1,192.54/28.24
6. Step 6: Final answer
   x = 42.23