Finding the Fourth Proportional to 72.88, 100.55 and 57.34

Step by Step Solution

1. Step 1: Write the proportion equation
   72.88 : 100.55 = 57.34 : x
2. Step 2: Convert to fraction form
   72.88/100.55 = 57.34/x
3. Step 3: Cross multiply
   72.88x = 100.55 × 57.34
4. Step 4: Simplify right side
   72.88x = 5,765.03
5. Step 5: Solve for x
   x = 5,765.03/72.88
6. Step 6: Final answer
   x = 79.11