Finding the Fourth Proportional to 80.98, 111.71 and 51.42

Step by Step Solution

1. Step 1: Write the proportion equation
   80.98 : 111.71 = 51.42 : x
2. Step 2: Convert to fraction form
   80.98/111.71 = 51.42/x
3. Step 3: Cross multiply
   80.98x = 111.71 × 51.42
4. Step 4: Simplify right side
   80.98x = 5,743.59
5. Step 5: Solve for x
   x = 5,743.59/80.98
6. Step 6: Final answer
   x = 70.93