Finding the Fourth Proportional to 21,513.08, 29,688.72 and 13,016.77

Step by Step Solution

1. Step 1: Write the proportion equation
   21,513.08 : 29,688.72 = 13,016.77 : x
2. Step 2: Convert to fraction form
   21,513.08/29,688.72 = 13,016.77/x
3. Step 3: Cross multiply
   21,513.08x = 29,688.72 × 13,016.77
4. Step 4: Simplify right side
   21,513.08x = 386,451,116.80
5. Step 5: Solve for x
   x = 386,451,116.80/21,513.08
6. Step 6: Final answer
   x = 17,963.54