Finding the Fourth Proportional to 72.06, 99.39 and 56.49

Step by Step Solution

1. Step 1: Write the proportion equation
   72.06 : 99.39 = 56.49 : x
2. Step 2: Convert to fraction form
   72.06/99.39 = 56.49/x
3. Step 3: Cross multiply
   72.06x = 99.39 × 56.49
4. Step 4: Simplify right side
   72.06x = 5,614.54
5. Step 5: Solve for x
   x = 5,614.54/72.06
6. Step 6: Final answer
   x = 77.91