Finding the Fourth Proportional to 151.56, 227.18 and 90.72

Step by Step Solution

1. Step 1: Write the proportion equation
   151.56 : 227.18 = 90.72 : x
2. Step 2: Convert to fraction form
   151.56/227.18 = 90.72/x
3. Step 3: Cross multiply
   151.56x = 227.18 × 90.72
4. Step 4: Simplify right side
   151.56x = 20,609.77
5. Step 5: Solve for x
   x = 20,609.77/151.56
6. Step 6: Final answer
   x = 135.98