Finding the Fourth Proportional to 39,866.61, 55,016.37 and 21,961.23

Step by Step Solution

1. Step 1: Write the proportion equation
   39,866.61 : 55,016.37 = 21,961.23 : x
2. Step 2: Convert to fraction form
   39,866.61/55,016.37 = 21,961.23/x
3. Step 3: Cross multiply
   39,866.61x = 55,016.37 × 21,961.23
4. Step 4: Simplify right side
   39,866.61x = 1,208,227,155.34
5. Step 5: Solve for x
   x = 1,208,227,155.34/39,866.61
6. Step 6: Final answer
   x = 30,306.74