Finding the Fourth Proportional to 78.72, 117.94 and 38.09

Step by Step Solution

1. Step 1: Write the proportion equation
   78.72 : 117.94 = 38.09 : x
2. Step 2: Convert to fraction form
   78.72/117.94 = 38.09/x
3. Step 3: Cross multiply
   78.72x = 117.94 × 38.09
4. Step 4: Simplify right side
   78.72x = 4,492.33
5. Step 5: Solve for x
   x = 4,492.33/78.72
6. Step 6: Final answer
   x = 57.07