Finding the Fourth Proportional to 78.95, 118.56 and 42.95

Step by Step Solution

1. Step 1: Write the proportion equation
   78.95 : 118.56 = 42.95 : x
2. Step 2: Convert to fraction form
   78.95/118.56 = 42.95/x
3. Step 3: Cross multiply
   78.95x = 118.56 × 42.95
4. Step 4: Simplify right side
   78.95x = 5,092.15
5. Step 5: Solve for x
   x = 5,092.15/78.95
6. Step 6: Final answer
   x = 64.50