Finding the Fourth Proportional to 13,111.27, 18,093.68 and 7,142.99

Step by Step Solution

1. Step 1: Write the proportion equation
   13,111.27 : 18,093.68 = 7,142.99 : x
2. Step 2: Convert to fraction form
   13,111.27/18,093.68 = 7,142.99/x
3. Step 3: Cross multiply
   13,111.27x = 18,093.68 × 7,142.99
4. Step 4: Simplify right side
   13,111.27x = 129,242,875.91
5. Step 5: Solve for x
   x = 129,242,875.91/13,111.27
6. Step 6: Final answer
   x = 9,857.39