Finding the Fourth Proportional to 78.76, 108.72 and 55.48

Step by Step Solution

1. Step 1: Write the proportion equation
   78.76 : 108.72 = 55.48 : x
2. Step 2: Convert to fraction form
   78.76/108.72 = 55.48/x
3. Step 3: Cross multiply
   78.76x = 108.72 × 55.48
4. Step 4: Simplify right side
   78.76x = 6,031.79
5. Step 5: Solve for x
   x = 6,031.79/78.76
6. Step 6: Final answer
   x = 76.58