Finding the Fourth Proportional to 72.79, 109.15 and 38.47

Step by Step Solution

1. Step 1: Write the proportion equation
   72.79 : 109.15 = 38.47 : x
2. Step 2: Convert to fraction form
   72.79/109.15 = 38.47/x
3. Step 3: Cross multiply
   72.79x = 109.15 × 38.47
4. Step 4: Simplify right side
   72.79x = 4,199.00
5. Step 5: Solve for x
   x = 4,199.00/72.79
6. Step 6: Final answer
   x = 57.69