Finding the Fourth Proportional to 102.56, 141.58 and 88.50

Step by Step Solution

1. Step 1: Write the proportion equation
   102.56 : 141.58 = 88.50 : x
2. Step 2: Convert to fraction form
   102.56/141.58 = 88.50/x
3. Step 3: Cross multiply
   102.56x = 141.58 × 88.50
4. Step 4: Simplify right side
   102.56x = 12,529.83
5. Step 5: Solve for x
   x = 12,529.83/102.56
6. Step 6: Final answer
   x = 122.17