Finding the Fourth Proportional to 78.99, 118.41 and 42.42

Step by Step Solution

1. Step 1: Write the proportion equation
   78.99 : 118.41 = 42.42 : x
2. Step 2: Convert to fraction form
   78.99/118.41 = 42.42/x
3. Step 3: Cross multiply
   78.99x = 118.41 × 42.42
4. Step 4: Simplify right side
   78.99x = 5,023.48
5. Step 5: Solve for x
   x = 5,023.48/78.99
6. Step 6: Final answer
   x = 63.59