Finding the Fourth Proportional to 78.29, 117.25 and 42.13

Step by Step Solution

1. Step 1: Write the proportion equation
   78.29 : 117.25 = 42.13 : x
2. Step 2: Convert to fraction form
   78.29/117.25 = 42.13/x
3. Step 3: Cross multiply
   78.29x = 117.25 × 42.13
4. Step 4: Simplify right side
   78.29x = 4,939.53
5. Step 5: Solve for x
   x = 4,939.53/78.29
6. Step 6: Final answer
   x = 63.09