Finding the Fourth Proportional to 9,002.09, 12,421.04 and 5,172.99

Step by Step Solution

1. Step 1: Write the proportion equation
   9,002.09 : 12,421.04 = 5,172.99 : x
2. Step 2: Convert to fraction form
   9,002.09/12,421.04 = 5,172.99/x
3. Step 3: Cross multiply
   9,002.09x = 12,421.04 × 5,172.99
4. Step 4: Simplify right side
   9,002.09x = 64,253,926.59
5. Step 5: Solve for x
   x = 64,253,926.59/9,002.09
6. Step 6: Final answer
   x = 7,137.66