Finding the Fourth Proportional to 21,016.35, 28,983.42 and 13,930.47

Step by Step Solution

1. Step 1: Write the proportion equation
   21,016.35 : 28,983.42 = 13,930.47 : x
2. Step 2: Convert to fraction form
   21,016.35/28,983.42 = 13,930.47/x
3. Step 3: Cross multiply
   21,016.35x = 28,983.42 × 13,930.47
4. Step 4: Simplify right side
   21,016.35x = 403,752,662.81
5. Step 5: Solve for x
   x = 403,752,662.81/21,016.35
6. Step 6: Final answer
   x = 19,211.36