Finding the Fourth Proportional to 90.81, 136.23 and 36.72

Step by Step Solution

1. Step 1: Write the proportion equation
   90.81 : 136.23 = 36.72 : x
2. Step 2: Convert to fraction form
   90.81/136.23 = 36.72/x
3. Step 3: Cross multiply
   90.81x = 136.23 × 36.72
4. Step 4: Simplify right side
   90.81x = 5,002.37
5. Step 5: Solve for x
   x = 5,002.37/90.81
6. Step 6: Final answer
   x = 55.09