Finding the Fourth Proportional to 109.72, 165.56 and 105.50

Step by Step Solution

1. Step 1: Write the proportion equation
   109.72 : 165.56 = 105.50 : x
2. Step 2: Convert to fraction form
   109.72/165.56 = 105.50/x
3. Step 3: Cross multiply
   109.72x = 165.56 × 105.50
4. Step 4: Simplify right side
   109.72x = 17,466.05
5. Step 5: Solve for x
   x = 17,466.05/109.72
6. Step 6: Final answer
   x = 159.19