Finding the Fourth Proportional to 78.86, 108.88 and 54.32

Step by Step Solution

1. Step 1: Write the proportion equation
   78.86 : 108.88 = 54.32 : x
2. Step 2: Convert to fraction form
   78.86/108.88 = 54.32/x
3. Step 3: Cross multiply
   78.86x = 108.88 × 54.32
4. Step 4: Simplify right side
   78.86x = 5,913.68
5. Step 5: Solve for x
   x = 5,913.68/78.86
6. Step 6: Final answer
   x = 74.99