Finding the Fourth Proportional to 78.74, 118.11 and 42.69

Step by Step Solution

1. Step 1: Write the proportion equation
   78.74 : 118.11 = 42.69 : x
2. Step 2: Convert to fraction form
   78.74/118.11 = 42.69/x
3. Step 3: Cross multiply
   78.74x = 118.11 × 42.69
4. Step 4: Simplify right side
   78.74x = 5,042.12
5. Step 5: Solve for x
   x = 5,042.12/78.74
6. Step 6: Final answer
   x = 64.04