Finding the Fourth Proportional to 39,870.50, 55,023.81 and 21,965.54

Step by Step Solution

1. Step 1: Write the proportion equation
   39,870.50 : 55,023.81 = 21,965.54 : x
2. Step 2: Convert to fraction form
   39,870.50/55,023.81 = 21,965.54/x
3. Step 3: Cross multiply
   39,870.50x = 55,023.81 × 21,965.54
4. Step 4: Simplify right side
   39,870.50x = 1,208,627,699.51
5. Step 5: Solve for x
   x = 1,208,627,699.51/39,870.50
6. Step 6: Final answer
   x = 30,313.83