Finding the Fourth Proportional to 21,026.50, 31,475.34 and 13,616.21

Step by Step Solution

1. Step 1: Write the proportion equation
   21,026.50 : 31,475.34 = 13,616.21 : x
2. Step 2: Convert to fraction form
   21,026.50/31,475.34 = 13,616.21/x
3. Step 3: Cross multiply
   21,026.50x = 31,475.34 × 13,616.21
4. Step 4: Simplify right side
   21,026.50x = 428,574,839.26
5. Step 5: Solve for x
   x = 428,574,839.26/21,026.50
6. Step 6: Final answer
   x = 20,382.60