Finding the Fourth Proportional to 20,910.96, 28,849.68 and 12,406.59

Step by Step Solution

1. Step 1: Write the proportion equation
   20,910.96 : 28,849.68 = 12,406.59 : x
2. Step 2: Convert to fraction form
   20,910.96/28,849.68 = 12,406.59/x
3. Step 3: Cross multiply
   20,910.96x = 28,849.68 × 12,406.59
4. Step 4: Simplify right side
   20,910.96x = 357,926,151.39
5. Step 5: Solve for x
   x = 357,926,151.39/20,910.96
6. Step 6: Final answer
   x = 17,116.68