Finding the Fourth Proportional to 72.42, 108.59 and 31.30

Step by Step Solution

1. Step 1: Write the proportion equation
   72.42 : 108.59 = 31.30 : x
2. Step 2: Convert to fraction form
   72.42/108.59 = 31.30/x
3. Step 3: Cross multiply
   72.42x = 108.59 × 31.30
4. Step 4: Simplify right side
   72.42x = 3,398.87
5. Step 5: Solve for x
   x = 3,398.87/72.42
6. Step 6: Final answer
   x = 46.93