Finding the Fourth Proportional to 39,723.39, 54,818.72 and 21,818.81

Step by Step Solution

1. Step 1: Write the proportion equation
   39,723.39 : 54,818.72 = 21,818.81 : x
2. Step 2: Convert to fraction form
   39,723.39/54,818.72 = 21,818.81/x
3. Step 3: Cross multiply
   39,723.39x = 54,818.72 × 21,818.81
4. Step 4: Simplify right side
   39,723.39x = 1,196,079,236.12
5. Step 5: Solve for x
   x = 1,196,079,236.12/39,723.39
6. Step 6: Final answer
   x = 30,110.20