Finding the Fourth Proportional to 11,981.21, 17,965.61 and 3,659.54

Step by Step Solution

1. Step 1: Write the proportion equation
   11,981.21 : 17,965.61 = 3,659.54 : x
2. Step 2: Convert to fraction form
   11,981.21/17,965.61 = 3,659.54/x
3. Step 3: Cross multiply
   11,981.21x = 17,965.61 × 3,659.54
4. Step 4: Simplify right side
   11,981.21x = 65,745,850.12
5. Step 5: Solve for x
   x = 65,745,850.12/11,981.21
6. Step 6: Final answer
   x = 5,487.41