Finding the Fourth Proportional to 22,939.21, 31,655.82 and 12,870.19

Step by Step Solution

1. Step 1: Write the proportion equation
   22,939.21 : 31,655.82 = 12,870.19 : x
2. Step 2: Convert to fraction form
   22,939.21/31,655.82 = 12,870.19/x
3. Step 3: Cross multiply
   22,939.21x = 31,655.82 × 12,870.19
4. Step 4: Simplify right side
   22,939.21x = 407,416,418.01
5. Step 5: Solve for x
   x = 407,416,418.01/22,939.21
6. Step 6: Final answer
   x = 17,760.70