Finding the Fourth Proportional to 72.71, 108.83 and 54.71

Step by Step Solution

1. Step 1: Write the proportion equation
   72.71 : 108.83 = 54.71 : x
2. Step 2: Convert to fraction form
   72.71/108.83 = 54.71/x
3. Step 3: Cross multiply
   72.71x = 108.83 × 54.71
4. Step 4: Simplify right side
   72.71x = 5,953.27
5. Step 5: Solve for x
   x = 5,953.27/72.71
6. Step 6: Final answer
   x = 81.88