Finding the Fourth Proportional to 102.56, 153.59 and 61.89

Step by Step Solution

1. Step 1: Write the proportion equation
   102.56 : 153.59 = 61.89 : x
2. Step 2: Convert to fraction form
   102.56/153.59 = 61.89/x
3. Step 3: Cross multiply
   102.56x = 153.59 × 61.89
4. Step 4: Simplify right side
   102.56x = 9,505.69
5. Step 5: Solve for x
   x = 9,505.69/102.56
6. Step 6: Final answer
   x = 92.68