Finding the Fourth Proportional to 11,919.99, 17,856.12 and 7,173.51

Step by Step Solution

1. Step 1: Write the proportion equation
   11,919.99 : 17,856.12 = 7,173.51 : x
2. Step 2: Convert to fraction form
   11,919.99/17,856.12 = 7,173.51/x
3. Step 3: Cross multiply
   11,919.99x = 17,856.12 × 7,173.51
4. Step 4: Simplify right side
   11,919.99x = 128,091,055.38
5. Step 5: Solve for x
   x = 128,091,055.38/11,919.99
6. Step 6: Final answer
   x = 10,745.90