Finding the Fourth Proportional to 21,158.02, 31,739.76 and 7,111.99

Step by Step Solution

1. Step 1: Write the proportion equation
   21,158.02 : 31,739.76 = 7,111.99 : x
2. Step 2: Convert to fraction form
   21,158.02/31,739.76 = 7,111.99/x
3. Step 3: Cross multiply
   21,158.02x = 31,739.76 × 7,111.99
4. Step 4: Simplify right side
   21,158.02x = 225,732,855.72
5. Step 5: Solve for x
   x = 225,732,855.72/21,158.02
6. Step 6: Final answer
   x = 10,668.90