Finding the Fourth Proportional to 39,897.83, 55,061.43 and 21,992.78

Step by Step Solution

1. Step 1: Write the proportion equation
   39,897.83 : 55,061.43 = 21,992.78 : x
2. Step 2: Convert to fraction form
   39,897.83/55,061.43 = 21,992.78/x
3. Step 3: Cross multiply
   39,897.83x = 55,061.43 × 21,992.78
4. Step 4: Simplify right side
   39,897.83x = 1,210,953,806.51
5. Step 5: Solve for x
   x = 1,210,953,806.51/39,897.83
6. Step 6: Final answer
   x = 30,351.37