Finding the Fourth Proportional to 78.98, 118.48 and 42.92

Step by Step Solution

1. Step 1: Write the proportion equation
   78.98 : 118.48 = 42.92 : x
2. Step 2: Convert to fraction form
   78.98/118.48 = 42.92/x
3. Step 3: Cross multiply
   78.98x = 118.48 × 42.92
4. Step 4: Simplify right side
   78.98x = 5,085.16
5. Step 5: Solve for x
   x = 5,085.16/78.98
6. Step 6: Final answer
   x = 64.39