Finding the Fourth Proportional to 78.83, 118.25 and 42.76

Step by Step Solution

1. Step 1: Write the proportion equation
   78.83 : 118.25 = 42.76 : x
2. Step 2: Convert to fraction form
   78.83/118.25 = 42.76/x
3. Step 3: Cross multiply
   78.83x = 118.25 × 42.76
4. Step 4: Simplify right side
   78.83x = 5,055.56
5. Step 5: Solve for x
   x = 5,055.56/78.83
6. Step 6: Final answer
   x = 64.13