Finding the Fourth Proportional to 111.98, 167.58 and 71.18

Step by Step Solution

1. Step 1: Write the proportion equation
   111.98 : 167.58 = 71.18 : x
2. Step 2: Convert to fraction form
   111.98/167.58 = 71.18/x
3. Step 3: Cross multiply
   111.98x = 167.58 × 71.18
4. Step 4: Simplify right side
   111.98x = 11,928.34
5. Step 5: Solve for x
   x = 11,928.34/111.98
6. Step 6: Final answer
   x = 106.52