Finding the Fourth Proportional to 78.98, 118.54 and 42.94

Step by Step Solution

1. Step 1: Write the proportion equation
   78.98 : 118.54 = 42.94 : x
2. Step 2: Convert to fraction form
   78.98/118.54 = 42.94/x
3. Step 3: Cross multiply
   78.98x = 118.54 × 42.94
4. Step 4: Simplify right side
   78.98x = 5,090.11
5. Step 5: Solve for x
   x = 5,090.11/78.98
6. Step 6: Final answer
   x = 64.45