Finding the Fourth Proportional to 101.55, 139.73 and 89.25

Step by Step Solution

1. Step 1: Write the proportion equation
   101.55 : 139.73 = 89.25 : x
2. Step 2: Convert to fraction form
   101.55/139.73 = 89.25/x
3. Step 3: Cross multiply
   101.55x = 139.73 × 89.25
4. Step 4: Simplify right side
   101.55x = 12,470.72
5. Step 5: Solve for x
   x = 12,470.72/101.55
6. Step 6: Final answer
   x = 122.80