Finding the Fourth Proportional to 107.20, 147.72 and 88.72

Step by Step Solution

1. Step 1: Write the proportion equation
   107.20 : 147.72 = 88.72 : x
2. Step 2: Convert to fraction form
   107.20/147.72 = 88.72/x
3. Step 3: Cross multiply
   107.20x = 147.72 × 88.72
4. Step 4: Simplify right side
   107.20x = 13,105.72
5. Step 5: Solve for x
   x = 13,105.72/107.20
6. Step 6: Final answer
   x = 122.25