Finding the Fourth Proportional to 83.09, 124.49 and 80.89

Step by Step Solution

1. Step 1: Write the proportion equation
   83.09 : 124.49 = 80.89 : x
2. Step 2: Convert to fraction form
   83.09/124.49 = 80.89/x
3. Step 3: Cross multiply
   83.09x = 124.49 × 80.89
4. Step 4: Simplify right side
   83.09x = 10,069.89
5. Step 5: Solve for x
   x = 10,069.89/83.09
6. Step 6: Final answer
   x = 121.19