Finding the Fourth Proportional to 109.14, 162.35 and 108.78

Step by Step Solution

1. Step 1: Write the proportion equation
   109.14 : 162.35 = 108.78 : x
2. Step 2: Convert to fraction form
   109.14/162.35 = 108.78/x
3. Step 3: Cross multiply
   109.14x = 162.35 × 108.78
4. Step 4: Simplify right side
   109.14x = 17,659.89
5. Step 5: Solve for x
   x = 17,659.89/109.14
6. Step 6: Final answer
   x = 161.81