Finding the Fourth Proportional to 111.69, 167.61 and 71.07

Step by Step Solution

1. Step 1: Write the proportion equation
   111.69 : 167.61 = 71.07 : x
2. Step 2: Convert to fraction form
   111.69/167.61 = 71.07/x
3. Step 3: Cross multiply
   111.69x = 167.61 × 71.07
4. Step 4: Simplify right side
   111.69x = 11,912.04
5. Step 5: Solve for x
   x = 11,912.04/111.69
6. Step 6: Final answer
   x = 106.65