Finding the Fourth Proportional to 21,015.37, 31,501.79 and 13,624.53

Step by Step Solution

1. Step 1: Write the proportion equation
   21,015.37 : 31,501.79 = 13,624.53 : x
2. Step 2: Convert to fraction form
   21,015.37/31,501.79 = 13,624.53/x
3. Step 3: Cross multiply
   21,015.37x = 31,501.79 × 13,624.53
4. Step 4: Simplify right side
   21,015.37x = 429,197,082.91
5. Step 5: Solve for x
   x = 429,197,082.91/21,015.37
6. Step 6: Final answer
   x = 20,423.01