Finding the Fourth Proportional to 22,890.29, 31,588.43 and 12,818.70

Step by Step Solution

1. Step 1: Write the proportion equation
   22,890.29 : 31,588.43 = 12,818.70 : x
2. Step 2: Convert to fraction form
   22,890.29/31,588.43 = 12,818.70/x
3. Step 3: Cross multiply
   22,890.29x = 31,588.43 × 12,818.70
4. Step 4: Simplify right side
   22,890.29x = 404,922,543.55
5. Step 5: Solve for x
   x = 404,922,543.55/22,890.29
6. Step 6: Final answer
   x = 17,689.71