Finding the Fourth Proportional to 78.72, 108.59 and 49.63

Step by Step Solution

1. Step 1: Write the proportion equation
   78.72 : 108.59 = 49.63 : x
2. Step 2: Convert to fraction form
   78.72/108.59 = 49.63/x
3. Step 3: Cross multiply
   78.72x = 108.59 × 49.63
4. Step 4: Simplify right side
   78.72x = 5,388.80
5. Step 5: Solve for x
   x = 5,388.80/78.72
6. Step 6: Final answer
   x = 68.46