Finding the Fourth Proportional to 71.82, 107.82 and 51.57

Step by Step Solution

1. Step 1: Write the proportion equation
   71.82 : 107.82 = 51.57 : x
2. Step 2: Convert to fraction form
   71.82/107.82 = 51.57/x
3. Step 3: Cross multiply
   71.82x = 107.82 × 51.57
4. Step 4: Simplify right side
   71.82x = 5,560.28
5. Step 5: Solve for x
   x = 5,560.28/71.82
6. Step 6: Final answer
   x = 77.42