Finding the Fourth Proportional to 21,859.56, 30,167.58 and 12,904.62

Step by Step Solution

1. Step 1: Write the proportion equation
   21,859.56 : 30,167.58 = 12,904.62 : x
2. Step 2: Convert to fraction form
   21,859.56/30,167.58 = 12,904.62/x
3. Step 3: Cross multiply
   21,859.56x = 30,167.58 × 12,904.62
4. Step 4: Simplify right side
   21,859.56x = 389,301,156.22
5. Step 5: Solve for x
   x = 389,301,156.22/21,859.56
6. Step 6: Final answer
   x = 17,809.19