Finding the Fourth Proportional to 13,097.28, 18,074.88 and 7,721.30

Step by Step Solution

1. Step 1: Write the proportion equation
   13,097.28 : 18,074.88 = 7,721.30 : x
2. Step 2: Convert to fraction form
   13,097.28/18,074.88 = 7,721.30/x
3. Step 3: Cross multiply
   13,097.28x = 18,074.88 × 7,721.30
4. Step 4: Simplify right side
   13,097.28x = 139,561,570.94
5. Step 5: Solve for x
   x = 139,561,570.94/13,097.28
6. Step 6: Final answer
   x = 10,655.77