Finding the Fourth Proportional to 111.61, 166.28 and 111.25

Step by Step Solution

1. Step 1: Write the proportion equation
   111.61 : 166.28 = 111.25 : x
2. Step 2: Convert to fraction form
   111.61/166.28 = 111.25/x
3. Step 3: Cross multiply
   111.61x = 166.28 × 111.25
4. Step 4: Simplify right side
   111.61x = 18,498.65
5. Step 5: Solve for x
   x = 18,498.65/111.61
6. Step 6: Final answer
   x = 165.74