Finding the Fourth Proportional to 86.01, 128.12 and 83.62

Step by Step Solution

1. Step 1: Write the proportion equation
   86.01 : 128.12 = 83.62 : x
2. Step 2: Convert to fraction form
   86.01/128.12 = 83.62/x
3. Step 3: Cross multiply
   86.01x = 128.12 × 83.62
4. Step 4: Simplify right side
   86.01x = 10,713.39
5. Step 5: Solve for x
   x = 10,713.39/86.01
6. Step 6: Final answer
   x = 124.56