Finding the Fourth Proportional to 111.33, 166.95 and 42.87

Step by Step Solution

1. Step 1: Write the proportion equation
   111.33 : 166.95 = 42.87 : x
2. Step 2: Convert to fraction form
   111.33/166.95 = 42.87/x
3. Step 3: Cross multiply
   111.33x = 166.95 × 42.87
4. Step 4: Simplify right side
   111.33x = 7,157.15
5. Step 5: Solve for x
   x = 7,157.15/111.33
6. Step 6: Final answer
   x = 64.29