Finding the Fourth Proportional to 71.82, 99.09 and 42.72

Step by Step Solution

1. Step 1: Write the proportion equation
   71.82 : 99.09 = 42.72 : x
2. Step 2: Convert to fraction form
   71.82/99.09 = 42.72/x
3. Step 3: Cross multiply
   71.82x = 99.09 × 42.72
4. Step 4: Simplify right side
   71.82x = 4,233.12
5. Step 5: Solve for x
   x = 4,233.12/71.82
6. Step 6: Final answer
   x = 58.94