Finding the Fourth Proportional to 111.30, 166.97 and 82.78

Step by Step Solution

1. Step 1: Write the proportion equation
   111.30 : 166.97 = 82.78 : x
2. Step 2: Convert to fraction form
   111.30/166.97 = 82.78/x
3. Step 3: Cross multiply
   111.30x = 166.97 × 82.78
4. Step 4: Simplify right side
   111.30x = 13,821.78
5. Step 5: Solve for x
   x = 13,821.78/111.30
6. Step 6: Final answer
   x = 124.18