Finding the Fourth Proportional to 78.27, 117.27 and 42.09

Step by Step Solution

1. Step 1: Write the proportion equation
   78.27 : 117.27 = 42.09 : x
2. Step 2: Convert to fraction form
   78.27/117.27 = 42.09/x
3. Step 3: Cross multiply
   78.27x = 117.27 × 42.09
4. Step 4: Simplify right side
   78.27x = 4,935.89
5. Step 5: Solve for x
   x = 4,935.89/78.27
6. Step 6: Final answer
   x = 63.06