Finding the Fourth Proportional to 111.39, 167.01 and 42.87

Step by Step Solution

1. Step 1: Write the proportion equation
   111.39 : 167.01 = 42.87 : x
2. Step 2: Convert to fraction form
   111.39/167.01 = 42.87/x
3. Step 3: Cross multiply
   111.39x = 167.01 × 42.87
4. Step 4: Simplify right side
   111.39x = 7,160.18
5. Step 5: Solve for x
   x = 7,160.18/111.39
6. Step 6: Final answer
   x = 64.28