Finding the Fourth Proportional to 72.37, 108.52 and 31.78

Step by Step Solution

1. Step 1: Write the proportion equation
   72.37 : 108.52 = 31.78 : x
2. Step 2: Convert to fraction form
   72.37/108.52 = 31.78/x
3. Step 3: Cross multiply
   72.37x = 108.52 × 31.78
4. Step 4: Simplify right side
   72.37x = 3,448.77
5. Step 5: Solve for x
   x = 3,448.77/72.37
6. Step 6: Final answer
   x = 47.65