Finding the Fourth Proportional to 86.01, 128.91 and 45.48

Step by Step Solution

1. Step 1: Write the proportion equation
   86.01 : 128.91 = 45.48 : x
2. Step 2: Convert to fraction form
   86.01/128.91 = 45.48/x
3. Step 3: Cross multiply
   86.01x = 128.91 × 45.48
4. Step 4: Simplify right side
   86.01x = 5,862.83
5. Step 5: Solve for x
   x = 5,862.83/86.01
6. Step 6: Final answer
   x = 68.16