Finding the Fourth Proportional to 72.48, 108.72 and 56.28

Step by Step Solution

1. Step 1: Write the proportion equation
   72.48 : 108.72 = 56.28 : x
2. Step 2: Convert to fraction form
   72.48/108.72 = 56.28/x
3. Step 3: Cross multiply
   72.48x = 108.72 × 56.28
4. Step 4: Simplify right side
   72.48x = 6,118.76
5. Step 5: Solve for x
   x = 6,118.76/72.48
6. Step 6: Final answer
   x = 84.42