Finding the Fourth Proportional to 21,819, 30,110.28 and 12,389.04

Step by Step Solution

1. Step 1: Write the proportion equation
   21,819 : 30,110.28 = 12,389.04 : x
2. Step 2: Convert to fraction form
   21,819/30,110.28 = 12,389.04/x
3. Step 3: Cross multiply
   21,819x = 30,110.28 × 12,389.04
4. Step 4: Simplify right side
   21,819x = 373,037,463.33
5. Step 5: Solve for x
   x = 373,037,463.33/21,819
6. Step 6: Final answer
   x = 17,096.91