Finding the Fourth Proportional to 90,011.72, 135,036.70 and 30,831.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,011.72 : 135,036.70 = 30,831.50 : x
2. Step 2: Convert to fraction form
   90,011.72/135,036.70 = 30,831.50/x
3. Step 3: Cross multiply
   90,011.72x = 135,036.70 × 30,831.50
4. Step 4: Simplify right side
   90,011.72x = 4,163,384,016.05
5. Step 5: Solve for x
   x = 4,163,384,016.05/90,011.72
6. Step 6: Final answer
   x = 46,253.80