Finding the Fourth Proportional to 21,111.53, 31,657.98 and 11,248.70

Step by Step Solution

1. Step 1: Write the proportion equation
   21,111.53 : 31,657.98 = 11,248.70 : x
2. Step 2: Convert to fraction form
   21,111.53/31,657.98 = 11,248.70/x
3. Step 3: Cross multiply
   21,111.53x = 31,657.98 × 11,248.70
4. Step 4: Simplify right side
   21,111.53x = 356,111,119.63
5. Step 5: Solve for x
   x = 356,111,119.63/21,111.53
6. Step 6: Final answer
   x = 16,868.09