Finding the Fourth Proportional to 12,690.17, 17,512.21 and 7,024.79

Step by Step Solution

1. Step 1: Write the proportion equation
   12,690.17 : 17,512.21 = 7,024.79 : x
2. Step 2: Convert to fraction form
   12,690.17/17,512.21 = 7,024.79/x
3. Step 3: Cross multiply
   12,690.17x = 17,512.21 × 7,024.79
4. Step 4: Simplify right side
   12,690.17x = 123,019,597.69
5. Step 5: Solve for x
   x = 123,019,597.69/12,690.17
6. Step 6: Final answer
   x = 9,694.09