Finding the Fourth Proportional to 78.86, 108.88 and 51.27

Step by Step Solution

1. Step 1: Write the proportion equation
   78.86 : 108.88 = 51.27 : x
2. Step 2: Convert to fraction form
   78.86/108.88 = 51.27/x
3. Step 3: Cross multiply
   78.86x = 108.88 × 51.27
4. Step 4: Simplify right side
   78.86x = 5,582.28
5. Step 5: Solve for x
   x = 5,582.28/78.86
6. Step 6: Final answer
   x = 70.79