Finding the Fourth Proportional to 91.27, 136.91 and 89.25

Step by Step Solution

1. Step 1: Write the proportion equation
   91.27 : 136.91 = 89.25 : x
2. Step 2: Convert to fraction form
   91.27/136.91 = 89.25/x
3. Step 3: Cross multiply
   91.27x = 136.91 × 89.25
4. Step 4: Simplify right side
   91.27x = 12,218.09
5. Step 5: Solve for x
   x = 12,218.09/91.27
6. Step 6: Final answer
   x = 133.87