Finding the Fourth Proportional to 13.31, 18.35 and 10.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13.31 : 18.35 = 10.72 : x
2. Step 2: Convert to fraction form
   13.31/18.35 = 10.72/x
3. Step 3: Cross multiply
   13.31x = 18.35 × 10.72
4. Step 4: Simplify right side
   13.31x = 196.71
5. Step 5: Solve for x
   x = 196.71/13.31
6. Step 6: Final answer
   x = 14.78