Finding the Fourth Proportional to 20,494.39, 28,271.56 and 12,938

Step by Step Solution

1. Step 1: Write the proportion equation
   20,494.39 : 28,271.56 = 12,938 : x
2. Step 2: Convert to fraction form
   20,494.39/28,271.56 = 12,938/x
3. Step 3: Cross multiply
   20,494.39x = 28,271.56 × 12,938
4. Step 4: Simplify right side
   20,494.39x = 365,777,443.28
5. Step 5: Solve for x
   x = 365,777,443.28/20,494.39
6. Step 6: Final answer
   x = 17,847.69