Finding the Fourth Proportional to 72.42, 108.58 and 31.83

Step by Step Solution

1. Step 1: Write the proportion equation
   72.42 : 108.58 = 31.83 : x
2. Step 2: Convert to fraction form
   72.42/108.58 = 31.83/x
3. Step 3: Cross multiply
   72.42x = 108.58 × 31.83
4. Step 4: Simplify right side
   72.42x = 3,456.10
5. Step 5: Solve for x
   x = 3,456.10/72.42
6. Step 6: Final answer
   x = 47.72