Finding the Fourth Proportional to 21,870.56, 32,806.34 and 7,831.54

Step by Step Solution

1. Step 1: Write the proportion equation
   21,870.56 : 32,806.34 = 7,831.54 : x
2. Step 2: Convert to fraction form
   21,870.56/32,806.34 = 7,831.54/x
3. Step 3: Cross multiply
   21,870.56x = 32,806.34 × 7,831.54
4. Step 4: Simplify right side
   21,870.56x = 256,924,163.96
5. Step 5: Solve for x
   x = 256,924,163.96/21,870.56
6. Step 6: Final answer
   x = 11,747.49