Finding the Fourth Proportional to 20,429.96, 28,185.18 and 12,874.28

Step by Step Solution

1. Step 1: Write the proportion equation
   20,429.96 : 28,185.18 = 12,874.28 : x
2. Step 2: Convert to fraction form
   20,429.96/28,185.18 = 12,874.28/x
3. Step 3: Cross multiply
   20,429.96x = 28,185.18 × 12,874.28
4. Step 4: Simplify right side
   20,429.96x = 362,863,899.17
5. Step 5: Solve for x
   x = 362,863,899.17/20,429.96
6. Step 6: Final answer
   x = 17,761.36