Finding the Fourth Proportional to 22,457.62, 30,990.37 and 12,890.86

Step by Step Solution

1. Step 1: Write the proportion equation
   22,457.62 : 30,990.37 = 12,890.86 : x
2. Step 2: Convert to fraction form
   22,457.62/30,990.37 = 12,890.86/x
3. Step 3: Cross multiply
   22,457.62x = 30,990.37 × 12,890.86
4. Step 4: Simplify right side
   22,457.62x = 399,492,646.06
5. Step 5: Solve for x
   x = 399,492,646.06/22,457.62
6. Step 6: Final answer
   x = 17,788.73