Finding the Fourth Proportional to 86.56, 119.52 and 64.72

Step by Step Solution

1. Step 1: Write the proportion equation
   86.56 : 119.52 = 64.72 : x
2. Step 2: Convert to fraction form
   86.56/119.52 = 64.72/x
3. Step 3: Cross multiply
   86.56x = 119.52 × 64.72
4. Step 4: Simplify right side
   86.56x = 7,735.33
5. Step 5: Solve for x
   x = 7,735.33/86.56
6. Step 6: Final answer
   x = 89.36