Finding the Fourth Proportional to 71.12, 106.72 and 55.12

Step by Step Solution

1. Step 1: Write the proportion equation
   71.12 : 106.72 = 55.12 : x
2. Step 2: Convert to fraction form
   71.12/106.72 = 55.12/x
3. Step 3: Cross multiply
   71.12x = 106.72 × 55.12
4. Step 4: Simplify right side
   71.12x = 5,882.41
5. Step 5: Solve for x
   x = 5,882.41/71.12
6. Step 6: Final answer
   x = 82.71