Finding the Fourth Proportional to 111.30, 166.98 and 78.84

Step by Step Solution

1. Step 1: Write the proportion equation
   111.30 : 166.98 = 78.84 : x
2. Step 2: Convert to fraction form
   111.30/166.98 = 78.84/x
3. Step 3: Cross multiply
   111.30x = 166.98 × 78.84
4. Step 4: Simplify right side
   111.30x = 13,164.70
5. Step 5: Solve for x
   x = 13,164.70/111.30
6. Step 6: Final answer
   x = 118.28