Finding the Fourth Proportional to 162.56, 243.78 and 90.56

Step by Step Solution

1. Step 1: Write the proportion equation
   162.56 : 243.78 = 90.56 : x
2. Step 2: Convert to fraction form
   162.56/243.78 = 90.56/x
3. Step 3: Cross multiply
   162.56x = 243.78 × 90.56
4. Step 4: Simplify right side
   162.56x = 22,076.72
5. Step 5: Solve for x
   x = 22,076.72/162.56
6. Step 6: Final answer
   x = 135.81