Finding the Fourth Proportional to 39,072.42, 53,919.89 and 21,167.49

Step by Step Solution

1. Step 1: Write the proportion equation
   39,072.42 : 53,919.89 = 21,167.49 : x
2. Step 2: Convert to fraction form
   39,072.42/53,919.89 = 21,167.49/x
3. Step 3: Cross multiply
   39,072.42x = 53,919.89 × 21,167.49
4. Step 4: Simplify right side
   39,072.42x = 1,141,348,626.54
5. Step 5: Solve for x
   x = 1,141,348,626.54/39,072.42
6. Step 6: Final answer
   x = 29,211.11