Finding the Fourth Proportional to 78.65, 118.01 and 42.06

Step by Step Solution

1. Step 1: Write the proportion equation
   78.65 : 118.01 = 42.06 : x
2. Step 2: Convert to fraction form
   78.65/118.01 = 42.06/x
3. Step 3: Cross multiply
   78.65x = 118.01 × 42.06
4. Step 4: Simplify right side
   78.65x = 4,963.29
5. Step 5: Solve for x
   x = 4,963.29/78.65
6. Step 6: Final answer
   x = 63.11