Finding the Fourth Proportional to 12,818.72, 17,690.51 and 7,515.25

Step by Step Solution

1. Step 1: Write the proportion equation
   12,818.72 : 17,690.51 = 7,515.25 : x
2. Step 2: Convert to fraction form
   12,818.72/17,690.51 = 7,515.25/x
3. Step 3: Cross multiply
   12,818.72x = 17,690.51 × 7,515.25
4. Step 4: Simplify right side
   12,818.72x = 132,948,579.84
5. Step 5: Solve for x
   x = 132,948,579.84/12,818.72
6. Step 6: Final answer
   x = 10,371.44