Finding the Fourth Proportional to 78.59, 108.42 and 54.02

Step by Step Solution

1. Step 1: Write the proportion equation
   78.59 : 108.42 = 54.02 : x
2. Step 2: Convert to fraction form
   78.59/108.42 = 54.02/x
3. Step 3: Cross multiply
   78.59x = 108.42 × 54.02
4. Step 4: Simplify right side
   78.59x = 5,856.85
5. Step 5: Solve for x
   x = 5,856.85/78.59
6. Step 6: Final answer
   x = 74.52