Finding the Fourth Proportional to 100.72, 151.28 and 86.27

Step by Step Solution

1. Step 1: Write the proportion equation
   100.72 : 151.28 = 86.27 : x
2. Step 2: Convert to fraction form
   100.72/151.28 = 86.27/x
3. Step 3: Cross multiply
   100.72x = 151.28 × 86.27
4. Step 4: Simplify right side
   100.72x = 13,050.93
5. Step 5: Solve for x
   x = 13,050.93/100.72
6. Step 6: Final answer
   x = 129.58