Finding the Fourth Proportional to 80.50, 120.83 and 42.58

Step by Step Solution

1. Step 1: Write the proportion equation
   80.50 : 120.83 = 42.58 : x
2. Step 2: Convert to fraction form
   80.50/120.83 = 42.58/x
3. Step 3: Cross multiply
   80.50x = 120.83 × 42.58
4. Step 4: Simplify right side
   80.50x = 5,144.94
5. Step 5: Solve for x
   x = 5,144.94/80.50
6. Step 6: Final answer
   x = 63.91