Finding the Fourth Proportional to 86.46, 119.34 and 83.89

Step by Step Solution

1. Step 1: Write the proportion equation
   86.46 : 119.34 = 83.89 : x
2. Step 2: Convert to fraction form
   86.46/119.34 = 83.89/x
3. Step 3: Cross multiply
   86.46x = 119.34 × 83.89
4. Step 4: Simplify right side
   86.46x = 10,011.43
5. Step 5: Solve for x
   x = 10,011.43/86.46
6. Step 6: Final answer
   x = 115.79