Finding the Fourth Proportional to 22,890.88, 31,590.84 and 13,456

Step by Step Solution

1. Step 1: Write the proportion equation
   22,890.88 : 31,590.84 = 13,456 : x
2. Step 2: Convert to fraction form
   22,890.88/31,590.84 = 13,456/x
3. Step 3: Cross multiply
   22,890.88x = 31,590.84 × 13,456
4. Step 4: Simplify right side
   22,890.88x = 425,086,343.04
5. Step 5: Solve for x
   x = 425,086,343.04/22,890.88
6. Step 6: Final answer
   x = 18,570.12