Finding the Fourth Proportional to 28.09, 42.42 and 28.09

Step by Step Solution

1. Step 1: Write the proportion equation
   28.09 : 42.42 = 28.09 : x
2. Step 2: Convert to fraction form
   28.09/42.42 = 28.09/x
3. Step 3: Cross multiply
   28.09x = 42.42 × 28.09
4. Step 4: Simplify right side
   28.09x = 1,191.58
5. Step 5: Solve for x
   x = 1,191.58/28.09
6. Step 6: Final answer
   x = 42.42