Finding the Fourth Proportional to 72.42, 108.66 and 42

Step by Step Solution

1. Step 1: Write the proportion equation
   72.42 : 108.66 = 42 : x
2. Step 2: Convert to fraction form
   72.42/108.66 = 42/x
3. Step 3: Cross multiply
   72.42x = 108.66 × 42
4. Step 4: Simplify right side
   72.42x = 4,563.72
5. Step 5: Solve for x
   x = 4,563.72/72.42
6. Step 6: Final answer
   x = 63.02