Finding the Fourth Proportional to 21,381.51, 29,487.25 and 13,819.89

Step by Step Solution

1. Step 1: Write the proportion equation
   21,381.51 : 29,487.25 = 13,819.89 : x
2. Step 2: Convert to fraction form
   21,381.51/29,487.25 = 13,819.89/x
3. Step 3: Cross multiply
   21,381.51x = 29,487.25 × 13,819.89
4. Step 4: Simplify right side
   21,381.51x = 407,510,568.68
5. Step 5: Solve for x
   x = 407,510,568.68/21,381.51
6. Step 6: Final answer
   x = 19,059.02