Finding the Fourth Proportional to 72.74, 108.84 and 54.56

Step by Step Solution

1. Step 1: Write the proportion equation
   72.74 : 108.84 = 54.56 : x
2. Step 2: Convert to fraction form
   72.74/108.84 = 54.56/x
3. Step 3: Cross multiply
   72.74x = 108.84 × 54.56
4. Step 4: Simplify right side
   72.74x = 5,938.31
5. Step 5: Solve for x
   x = 5,938.31/72.74
6. Step 6: Final answer
   x = 81.64